When publishing changes through a artition root, we should use the row
filter for the top-most ancestor. The relation may be added to multiple
publications, using different ancestors, and 52e4f0cd47 handled this
incorrectly. With c91f71b9dc we find the correct top-most ancestor, but
the code tried to fetch the row filter from all publications, including
those using a different ancestor etc. No row filter can be found for
such publications, which was treated as replicating all rows.
Similarly to c91f71b9dc, this seems to be a rare issue in practice. It
requires multiple publications including the same partitioned relation,
through different ancestors.
Fixed by only passing publications containing the top-most ancestor to
pgoutput_row_filter_init(), so that treating a missing row filter as
replicating all rows is correct.
Report and fix by me, test case by Hou zj. Reviews and improvements by
Amit Kapila.
Author: Tomas Vondra, Hou zj, Amit Kapila
Reviewed-by: Amit Kapila, Hou zj
Discussion: https://postgr.es/m/d26d24dd-2fab-3c48-0162-2b7f84a9c893%40enterprisedb.com
Commit 83fd4532a7 allowed publishing of changes via ancestors, for
publications defined with publish_via_partition_root. But the way
the ancestor was determined in get_rel_sync_entry() was incorrect,
simply updating the same variable. So with multiple publications,
replicating different ancestors, the outcome depended on the order
of publications in the list - the value from the last loop was used,
even if it wasn't the top-most ancestor.
This is a probably rare situation, as in most cases publications do
not overlap, so each partition has exactly one candidate ancestor
to replicate as and there's no ambiguity.
Fixed by tracking the "ancestor level" for each publication, and
picking the top-most ancestor. Adds a test case, verifying the
correct ancestor is used for publishing the changes and that this
does not depend on order of publications in the list.
Older releases have another bug in this loop - once all actions are
replicated, the loop is terminated, on the assumption that inspecting
additional publications is unecessary. But that misses the fact that
those additional applications may replicate different ancestors.
Fixed by removal of this break condition. We might still terminate the
loop in some cases (e.g. when replicating all actions and the ancestor
is the partition root).
Backpatch to 13, where publish_via_partition_root was introduced.
Initial report and fix by me, test added by Hou zj. Reviews and
improvements by Amit Kapila.
Author: Tomas Vondra, Hou zj, Amit Kapila
Reviewed-by: Amit Kapila, Hou zj
Discussion: https://postgr.es/m/d26d24dd-2fab-3c48-0162-2b7f84a9c893%40enterprisedb.com
Commit 3500ccc39b allowed for base backup
targets, meaning that we could do something with the backup other than
send it to the client, but all of those targets had to be baked in to
the core code. This commit makes it possible for extensions to define
additional backup targets.
Patch by me, reviewed by Abhijit Menon-Sen.
Discussion: http://postgr.es/m/CA+TgmoaqvdT-u3nt+_kkZ7bgDAyqDB0i-+XOMmr5JN2Rd37hxw@mail.gmail.com
These tests were added recently, but older code tests USE_LZ4 rathr
than HAVE_LIBLZ4, so let's follow the established precedent. It
also seems more consistent with the intent of the configure tests,
since I think that the USE_* symbols are intended to correspond to
what the user requested, and the HAVE_* symbols to what configure
found while probing.
Discussion: http://postgr.es/m/CA+Tgmoap+hTD2-QNPJLH4tffeFE8MX5+xkbFKMU3FKBy=ZSNKA@mail.gmail.com
Logical replication apply workers for a subscription can easily get stuck
in an infinite loop of attempting to apply a change, triggering an error
(such as a constraint violation), exiting with the error written to the
subscription server log, and restarting.
To partially remedy the situation, this patch adds a new subscription
option named 'disable_on_error'. To be consistent with old behavior, this
option defaults to false. When true, both the tablesync worker and apply
worker catch any errors thrown and disable the subscription in order to
break the loop. The error is still also written in the logs.
Once the subscription is disabled, users can either manually resolve the
conflict/error or skip the conflicting transaction by using
pg_replication_origin_advance() function. After resolving the conflict,
users need to enable the subscription to allow apply process to proceed.
Author: Osumi Takamichi and Mark Dilger
Reviewed-by: Greg Nancarrow, Vignesh C, Amit Kapila, Wang wei, Tang Haiying, Peter Smith, Masahiko Sawada, Shi Yu
Discussion : https://postgr.es/m/DB35438F-9356-4841-89A0-412709EBD3AB%40enterprisedb.com
Both client-side compression and server-side compression are now
supported for zstd. In addition, a backup compressed by the server
using zstd can now be decompressed by the client in order to
accommodate the use of -Fp.
Jeevan Ladhe, with some edits by me.
Discussion: http://postgr.es/m/CA+Tgmobyzfbz=gyze2_LL1ZumZunmaEKbHQxjrFkOR7APZGu-g@mail.gmail.com
This commits adds both the finish LSN (commit_lsn in case transaction got
committed, prepare_lsn in case of a prepared transaction, etc.) and
replication origin name to the existing error context message.
This will help users in specifying the origin name and transaction finish
LSN to pg_replication_origin_advance() SQL function to skip a particular
transaction.
Author: Masahiko Sawada
Reviewed-by: Takamichi Osumi, Euler Taveira, and Amit Kapila
Discussion: https://postgr.es/m/CAD21AoBarBf2oTF71ig2g_o=3Z_Dt6_sOpMQma1kFgbnA5OZ_w@mail.gmail.com
Previously, the message for logical replication worker errcontext is
incrementally built, which was not translation friendly. Instead, we use
complete sentences with if-else branches.
We also remove the commit timestamp from the context message since it's
not important information and made the message long.
Author: Masahiko Sawada
Reviewed-by: Takamichi Osumi, and Amit Kapila
Discussion: https://postgr.es/m/CAD21AoBarBf2oTF71ig2g_o=3Z_Dt6_sOpMQma1kFgbnA5OZ_w@mail.gmail.com
Set-returning functions that use the Materialize mode, creating a
tuplestore to include all the tuples returned in a set rather than doing
so in multiple calls, use roughly the same set of steps to prepare
ReturnSetInfo for this job:
- Check if ReturnSetInfo supports returning a tuplestore and if the
materialize mode is enabled.
- Create a tuplestore for all the tuples part of the returned set in the
per-query memory context, stored in ReturnSetInfo->setResult.
- Build a tuple descriptor mostly from get_call_result_type(), then
stored in ReturnSetInfo->setDesc. Note that there are some cases where
the SRF's tuple descriptor has to be the one specified by the function
caller.
This refactoring is done so as there are (well, should be) no behavior
changes in any of the in-core functions refactored, and the centralized
function that checks and sets up the function's ReturnSetInfo can be
controlled with a set of bits32 options. Two of them prove to be
necessary now:
- SRF_SINGLE_USE_EXPECTED to use expectedDesc as tuple descriptor, as
expected by the function's caller.
- SRF_SINGLE_BLESS to validate the tuple descriptor for the SRF.
The same initialization pattern is simplified in 28 places per my
count as of src/backend/, shaving up to ~900 lines of code. These
mostly come from the removal of the per-query initializations and the
sanity checks now grouped in a single location. There are more
locations that could be simplified in contrib/, that are left for a
follow-up cleanup.
fcc2817, 07daca5 and d61a361 have prepared the areas of the code related
to this change, to ease this refactoring.
Author: Melanie Plageman, Michael Paquier
Reviewed-by: Álvaro Herrera, Justin Pryzby
Discussion: https://postgr.es/m/CAAKRu_azyd1Z3W_r7Ou4sorTjRCs+PxeHw1CWJeXKofkE6TuZg@mail.gmail.com
It was decided (refer to the Discussion link below) that the stats
collector is not an appropriate place to store the error information of
subscription workers.
This patch changes the pg_stat_subscription_workers view (introduced by
commit 8d74fc96db) so that it stores only statistics counters:
apply_error_count and sync_error_count, and has one entry for
each subscription. The removed error information such as error-XID and
the error message would be stored in another way in the future which is
more reliable and persistent.
After removing these error details, there is no longer any relation
information, so the subscription statistics are now a cluster-wide
statistics.
The patch also changes the view name to pg_stat_subscription_stats since
the word "worker" is an implementation detail that we use one worker for
one tablesync and one apply.
Author: Masahiko Sawada, based on suggestions by Andres Freund
Reviewed-by: Peter Smith, Haiying Tang, Takamichi Osumi, Amit Kapila
Discussion: https://postgr.es/m/20220125063131.4cmvsxbz2tdg6g65@alap3.anarazel.de
See also afdeff1052. Failures after that commit provided a few more hints,
but not yet enough to understand what's going on.
In 019_replslot_limit.pl shut down nodes with fast instead of immediate mode
if we observe the failure mode. That should tell us whether the failures we're
observing are just a timing issue under high load. PGCTLTIMEOUT should prevent
buildfarm animals from hanging endlessly.
Also adds a bit more logging to replication slot drop and ShutdownPostgres().
Discussion: https://postgr.es/m/20220225192941.hqnvefgdzaro6gzg@alap3.anarazel.de
I have not been able to reproduce the occasional failures of
019_replslot_limit.pl we are seeing in the buildfarm and not for lack of
trying. The additional logging and increased log level will hopefully help.
Will be reverted once the cause is identified.
Discussion: https://postgr.es/m/20220218231415.c4plkp4i3reqcwip@alap3.anarazel.de
This feature adds row filtering for publication tables. When a publication
is defined or modified, an optional WHERE clause can be specified. Rows
that don't satisfy this WHERE clause will be filtered out. This allows a
set of tables to be partially replicated. The row filter is per table. A
new row filter can be added simply by specifying a WHERE clause after the
table name. The WHERE clause must be enclosed by parentheses.
The row filter WHERE clause for a table added to a publication that
publishes UPDATE and/or DELETE operations must contain only columns that
are covered by REPLICA IDENTITY. The row filter WHERE clause for a table
added to a publication that publishes INSERT can use any column. If the
row filter evaluates to NULL, it is regarded as "false". The WHERE clause
only allows simple expressions that don't have user-defined functions,
user-defined operators, user-defined types, user-defined collations,
non-immutable built-in functions, or references to system columns. These
restrictions could be addressed in the future.
If you choose to do the initial table synchronization, only data that
satisfies the row filters is copied to the subscriber. If the subscription
has several publications in which a table has been published with
different WHERE clauses, rows that satisfy ANY of the expressions will be
copied. If a subscriber is a pre-15 version, the initial table
synchronization won't use row filters even if they are defined in the
publisher.
The row filters are applied before publishing the changes. If the
subscription has several publications in which the same table has been
published with different filters (for the same publish operation), those
expressions get OR'ed together so that rows satisfying any of the
expressions will be replicated.
This means all the other filters become redundant if (a) one of the
publications have no filter at all, (b) one of the publications was
created using FOR ALL TABLES, (c) one of the publications was created
using FOR ALL TABLES IN SCHEMA and the table belongs to that same schema.
If your publication contains a partitioned table, the publication
parameter publish_via_partition_root determines if it uses the partition's
row filter (if the parameter is false, the default) or the root
partitioned table's row filter.
Psql commands \dRp+ and \d <table-name> will display any row filters.
Author: Hou Zhijie, Euler Taveira, Peter Smith, Ajin Cherian
Reviewed-by: Greg Nancarrow, Haiying Tang, Amit Kapila, Tomas Vondra, Dilip Kumar, Vignesh C, Alvaro Herrera, Andres Freund, Wei Wang
Discussion: https://www.postgresql.org/message-id/flat/CAHE3wggb715X%2BmK_DitLXF25B%3DjE6xyNCH4YOwM860JR7HarGQ%40mail.gmail.com
This routine is a no-op since dd04e95 from 2003, with a macro kept
around for compatibility purposes. This has led to the same code
patterns being copy-pasted around for no effect, sometimes in confusing
ways like in pg_logical_slot_get_changes_guts() from logical.c where the
code was actually incorrect.
This issue has been discussed on two different threads recently, so
rather than living with this legacy, remove any uses of this routine in
the C code to simplify things. The compatibility macro is kept to avoid
breaking any out-of-core modules that depend on it.
Reported-by: Tatsuhito Kasahara, Justin Pryzby
Author: Tatsuhito Kasahara
Discussion: https://postgr.es/m/20211217200419.GQ17618@telsasoft.com
Discussion: https://postgr.es/m/CAP0=ZVJeeYfAeRfmzqAF2Lumdiv4S4FewyBnZd4DPTrsSQKJKw@mail.gmail.com
This moves the functions related to performing WAL recovery into the new
xlogrecovery.c source file, leaving xlog.c responsible for maintaining
the WAL buffers, coordinating the startup and switch from recovery to
normal operations, and other miscellaneous stuff that have always been in
xlog.c.
Reviewed-by: Andres Freund, Kyotaro Horiguchi, Robert Haas
Discussion: https://www.postgresql.org/message-id/a31f27b4-a31d-f976-6217-2b03be646ffa%40iki.fi
Previously, replication slots were released in ProcKill() on error, resulting
in reporting replication slot drop of ephemeral slots after the stats
subsystem was already shut down.
To fix this problem, move replication slot release to a before_shmem_exit()
hook that is called before the stats collector shuts down. There wasn't really
a good reason for the slot handling to be in ProcKill() anyway.
Patch by Masahiko Sawada, with very minor polishing by me.
I, Andres, wrote a test for dropping slots during process exit, but there may
be some OS dependent issues around the number of times FATAL error messages
are displayed due to a still debated libpq issue. So that test will be
committed separately / later.
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-By: Andres Freund <andres@anarazel.de>
Author: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAD21AoDAeEpAbZEyYJsPZJUmSPaRicVSBObaL7sPaofnKz+9zg@mail.gmail.com
Move scanint8() to numutils.c and rename to pg_strtoint64(). We
already have a "16" and "32" version of that, and the code inside the
functions was aligned, so this move makes all three versions
consistent. The API is also changed to no longer provide the errorOK
case. Users that need the error checking can use strtoi64().
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/b239564c-cad0-b23e-c57e-166d883cb97d@enterprisedb.com
Depending on compiler version and optimization level, we might
get a complaint that lazy_scan_heap's "freespace" is used
uninitialized.
Compilers not aware that ereport(ERROR) doesn't return complained
about bbsink_lz4_new().
Assigning "-1" to a uint64 value has unportable results; fortunately,
the value of xlogreadsegno is unimportant when xlogreadfd is -1.
(It looks to me like there is no need for xlogreadsegno to be static
in the first place, but I didn't venture to change that.)
LZ4 compression can be a lot faster than gzip compression, so users
may prefer it even if the compression ratio is not as good. We will
want pg_basebackup to support LZ4 compression and decompression on the
client side as well, and there is a pending patch for that, but it's
by a different author, so I am committing this part separately for
that reason.
Jeevan Ladhe, reviewed by Tushar Ahuja and by me.
Discussion: http://postgr.es/m/CANm22Cg9cArXEaYgHVZhCnzPLfqXCZLAzjwTq7Fc0quXRPfbxA@mail.gmail.com
This extends the logical decoding to also decode sequence increments.
We differentiate between sequences created in the current (in-progress)
transaction, and sequences created earlier. This mixed behavior is
necessary because while sequences are not transactional (increments are
not subject to ROLLBACK), relfilenode changes are. So we do this:
* Changes for sequences created in the same top-level transaction are
treated as transactional, i.e. just like any other change from that
transaction, and discarded in case of a rollback.
* Changes for sequences created earlier are applied immediately, as if
performed outside any transaction. This applies also after ALTER
SEQUENCE, which may create a new relfilenode.
Moreover, if we ever get support for DDL replication, the sequence
won't exist until the transaction gets applied.
Sequences created in the current transaction are tracked in a simple
hash table, identified by a relfilenode. That means a sequence may
already exist, but if a transaction does ALTER SEQUENCE then the
increments for the new relfilenode will be treated as transactional.
For each relfilenode we track the XID of (sub)transaction that created
it, which is needed for cleanup at transaction end. We don't need to
check the XID to decide if an increment is transactional - if we find a
match in the hash table, it has to be the same transaction.
This requires two minor changes to WAL-logging. Firstly, we need to
ensure the sequence record has a valid XID - until now the the increment
might have XID 0 if it was the first change in a subxact. But the
sequence might have been created in the same top-level transaction. So
we ensure the XID is assigned when WAL-logging increments.
The other change is addition of "created" flag, marking increments for
newly created relfilenodes. This makes it easier to maintain the hash
table of sequences that need transactional handling.
Note: This is needed because of subxacts. A XID 0 might still have the
sequence created in a different subxact of the same top-level xact.
This does not include any changes to test_decoding and/or the built-in
replication - those will be committed in separate patches.
A patch adding decoding of sequences was originally submitted by Cary
Huang. This commit reworks various important aspects (e.g. the WAL
logging and transactional/non-transactional handling). However, the
original patch and reviews were very useful.
Author: Tomas Vondra, Cary Huang
Reviewed-by: Peter Eisentraut, Hannu Krosing, Andres Freund
Discussion: https://postgr.es/m/d045f3c2-6cfb-06d3-5540-e63c320df8bc@enterprisedb.com
Discussion: https://postgr.es/m/1710ed7e13b.cd7177461430746.3372264562543607781@highgo.ca
Commit 0ba281cb4b added a new syntax
for the BASE_BACKUP command, with extensible options, but maintained
support for the legacy syntax. This isn't important for PostgreSQL,
where pg_basebackup works with older server versions but not newer
ones, but it could in theory matter for out-of-core users of the
replication protocol.
Discussion on pgsql-hackers, however, suggests that no one is aware
of any out-of-core use of the BASE_BACKUP command, and the consensus
is in favor of removing support for the old syntax to simplify the
code, so do that.
Discussion: http://postgr.es/m/CA+TgmoazKcKUWtqVa0xZqSzbKgTH+X-aw4V7GyLD68EpDLMh8A@mail.gmail.com
Fix the following issues in pgoutput.c:
* rel_sync_cache_relation_cb does the wrong thing when called for a cache
flush (i.e., relid == 0). Instead of invalidating all RelationSyncCache
entries as it should, it does nothing.
* When rel_sync_cache_relation_cb does invalidate an entry, it immediately
zaps the entry->map structure, even though that might still be in use. We
instead just mark the entry as invalid and rebuild it at a later safe
point.
* Similarly, rel_sync_cache_publication_cb is way too eager to reset the
pubactions flags, which would likely lead to failing to transmit changes
that we should transmit. In this case also, we just mark the entry as
invalid and rebuild it at a later safe point.
Author: Tom Lane
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/885288.1641420714@sss.pgh.pa.us
When this code executed as superuser it appeared to work because no
system catalog lookups happened, but otherwise it crashes because there
is no transaction environment. Fix that.
Report and code change by me. Test case by Dagfinn Ilmari Mannsåker.
Discussion: http://postgr.es/m/CA+TgmobiKLXne-2AVzYyWRiO8=rChBQ=7ywoxp=2SmcFw=oDDw@mail.gmail.com
xlog.h is directly and indirectly #included in a lot of places. With
this change, xloginsert.h is no longer unnecessarily included in the
large number of them that don't need it.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/CALj2ACVe-W+WM5P44N7eG9C2_FmaeM8Dq5aCnD3fHt0Ba=WR6w@mail.gmail.com
I had made it depend on superuser, but that seems clearly inferior.
Also document the permissions requirement in the straming replication
protocol section of the documentation, rather than only in the
section having to do with pg_basebackup.
Idea and patch from Dagfinn Ilmari Mannsåker.
Discussion: http://postgr.es/m/87bkzw160u.fsf@wibble.ilmari.org
This fixes a set of issues that have accumulated over the past months
(or years) in various code areas. Most fixes are related to some recent
additions, as of the development of v15.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20220124030001.GQ23027@telsasoft.com
In logical replication mode, a WalSender is supposed to be able
to execute any regular SQL command, as well as the special
replication commands. Poor design of the replication-command
parser caused it to fail in various cases, notably:
* semicolons embedded in a command, or multiple SQL commands
sent in a single message;
* dollar-quoted literals containing odd numbers of single
or double quote marks;
* commands starting with a comment.
The basic problem here is that we're trying to run repl_scanner.l
across the entire input string even when it's not a replication
command. Since repl_scanner.l does not understand all of the
token types known to the core lexer, this is doomed to have
failure modes.
We certainly don't want to make repl_scanner.l as big as scan.l,
so instead rejigger stuff so that we only lex the first token of
a non-replication command. That will usually look like an IDENT
to repl_scanner.l, though a comment would end up getting reported
as a '-' or '/' single-character token. If the token is a replication
command keyword, we push it back and proceed normally with repl_gram.y
parsing. Otherwise, we can drop out of exec_replication_command()
without examining the rest of the string.
(It's still theoretically possible for repl_scanner.l to fail on
the first token; but that could only happen if it's an unterminated
single- or double-quoted string, in which case you'd have gotten
largely the same error from the core lexer too.)
In this way, repl_gram.y isn't involved at all in handling general
SQL commands, so we can get rid of the SQLCmd node type. (In
the back branches, we can't remove it because renumbering enum
NodeTag would be an ABI break; so just leave it sit there unused.)
I failed to resist the temptation to clean up some other sloppy
coding in repl_scanner.l while at it. The only externally-visible
behavior change from that is it now accepts \r and \f as whitespace,
same as the core lexer.
Per bug #17379 from Greg Rychlewski. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/17379-6a5c6cfb3f1f5e77@postgresql.org
pg_basebackup's --compression option now lets you write either
"client-gzip" or "server-gzip" instead of just "gzip" to specify
where the compression should be performed. If you write simply
"gzip" it's taken to mean "client-gzip" unless you also use
--target, in which case it is interpreted to mean "server-gzip",
because that's the only thing that makes any sense in that case.
To make this work, the BASE_BACKUP command now takes new
COMPRESSION and COMPRESSION_LEVEL options.
At present, pg_basebackup cannot decompress .gz files, so
server-side compression will cause a failure if (1) -Ft is not
used or (2) -R is used or (3) -D- is used without --no-manifest.
Along the way, I removed the information message added by commit
5c649fe153 which occurred if you
specified no compression level and told you that the default level
had been used instead. That seemed like more output than most
people would want.
Also along the way, this adds a check to the server for
unrecognized base backup options. This repairs a bug introduced
by commit 0ba281cb4b.
This commit also adds some new test cases for pg_verifybackup.
They take a server-side backup with and without compression, and
then extract the backup if we have the OS facilities available
to do so, and then run pg_verifybackup on the extracted
directory. That is a good test of the functionality added by
this commit and also improves test coverage for the backup target
patch (commit 3500ccc39b) and for
pg_verifybackup itself.
Patch by me, with a bug fix by Jeevan Ladhe. The patch set of which
this is a part has also had review and/or testing from Tushar Ahuja,
Suraj Kharage, Dipesh Pandit, and Mark Dilger.
Discussion: http://postgr.es/m/CA+Tgmoa-ST7fMLsVJduOB7Eub=2WjfpHS+QxHVEpUoinf4bOSg@mail.gmail.com
Without this, we get odd behavior when the previous cycle of
lexing exited in a non-default exclusive state. Every other
copy of this code is aware that it has to do BEGIN(INITIAL),
but repl_scanner.l did not get that memo.
The real-world impact of this is probably limited, since most
replication clients would abandon their connection after getting
a syntax error. Still, it's a bug.
This mistake is old, so back-patch to all supported branches.
Discussion: https://postgr.es/m/1874781.1643035952@sss.pgh.pa.us
Commit 5c649fe15 introduced a memory leak into pg_basebackup's
parse_compress_options. (I simplified nearby code while at it.)
Commit 9a974cbcb introduced a memory leak into pg_dump's
binary_upgrade_set_pg_class_oids.
Coverity also complained about a call of SnapBuildProcessChange that
ignored the result, unlike every other call of that function. This
is evidently intentional, so add a (void) cast to indicate that.
(It's also old, dating to b89e15105; I suppose the reason it showed
up now is 7a5f6b474's recent rearrangement of nearby code.)
pg_basebackup now has a --target=TARGET[:DETAIL] option. If specfied,
it is sent to the server as the value of the TARGET option to the
BASE_BACKUP command. If DETAIL is included, it is sent as the value of
the new TARGET_DETAIL option to the BASE_BACKUP command. If the
target is anything other than 'client', pg_basebackup assumes that it
will now be the server's job to write the backup in a location somehow
defined by the target, and that it therefore needs to write nothing
locally. However, the server will still send messages to the client
for progress reporting purposes.
On the server side, we now support two additional types of backup
targets. There is a 'blackhole' target, which just throws away the
backup data without doing anything at all with it. Naturally, this
should only be used for testing and debugging purposes, since you will
not actually have a backup when it finishes running. More usefully,
there is also a 'server' target, so you can now use something like
'pg_basebackup -Xnone -t server:/SOME/PATH' to write a backup to some
location on the server. We can extend this to more types of targets
in the future, and might even want to create an extensibility
mechanism for adding new target types.
Since WAL fetching is handled with separate client-side logic, it's
not part of this mechanism; thus, backups with non-default targets
must use -Xnone or -Xfetch.
Patch by me, with a bug fix by Jeevan Ladhe. The patch set of which
this is a part has also had review and/or testing from Tushar Ahuja,
Suraj Kharage, Dipesh Pandit, and Mark Dilger.
Discussion: http://postgr.es/m/CA+TgmoaYZbz0=Yk797aOJwkGJC-LK3iXn+wzzMx7KdwNpZhS5g@mail.gmail.com
bbsink_copystream wants to store a type byte just before the buffer,
but basebackup.c wants the buffer to be aligned so that it can call
PageIsNew() and PageGetLSN() on it. Therefore, instead of inserting
1 extra byte before the buffer, insert MAXIMUM_ALIGNOF extra bytes
and only use the last one.
On most machines this doesn't cause any problem (except perhaps for
performance) but some buildfarm machines with -fsanitize=alignment
dump core.
Discussion: http://postgr.es/m/CA+TgmoYx5=1A2K9JYV-9zdhyokU4KKTyNQ9q7CiXrX=YBBMWVw@mail.gmail.com
In the new approach, all files across all tablespaces are sent in a
single COPY OUT operation. The CopyData messages are no longer raw
archive content; rather, each message is prefixed with a type byte
that describes its purpose, e.g. 'n' signifies the start of a new
archive and 'd' signifies archive or manifest data. This protocol
is significantly more extensible than the old approach, since we can
later create more message types, though not without concern for
backward compatibility.
The new protocol sends a few things to the client that the old one
did not. First, it sends the name of each archive explicitly, instead
of letting the client compute it. This is intended to make it easier
to write future patches that might send archives in a format other
that tar (e.g. cpio, pax, tar.gz). Second, it sends explicit progress
messages rather than allowing the client to assume that progress is
defined by the number of bytes received. This will help with future
features where the server compresses the data, or sends it someplace
directly rather than transmitting it to the client.
The old protocol is still supported for compatibility with previous
releases. The new protocol is selected by means of a new
TARGET option to the BASE_BACKUP command. Currently, the
only supported target is 'client'. Support for additional
targets will be added in a later commit.
Patch by me. The patch set of which this is a part has had review
and/or testing from Jeevan Ladhe, Tushar Ahuja, Suraj Kharage,
Dipesh Pandit, and Mark Dilger.
Discussion: http://postgr.es/m/CA+TgmoaYZbz0=Yk797aOJwkGJC-LK3iXn+wzzMx7KdwNpZhS5g@mail.gmail.com
Before, SQL-level boolean constants were represented by a string with
a cast, and internal Boolean values in DDL commands were usually
represented by Integer nodes. This takes the place of both of these
uses, making the intent clearer and having some amount of type safety.
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/8c1a2e37-c68d-703c-5a83-7a6077f4f997@enterprisedb.com
The existing cryptohash facility was causing problems in some code paths
related to MD5 (frontend and backend) that relied on the fact that the
only type of error that could happen would be an OOM, as the MD5
implementation used in PostgreSQL ~13 (the in-core implementation is
used when compiling with or without OpenSSL in those older versions),
could fail only under this circumstance.
The new cryptohash facilities can fail for reasons other than OOMs, like
attempting MD5 when FIPS is enabled (upstream OpenSSL allows that up to
1.0.2, Fedora and Photon patch OpenSSL 1.1.1 to allow that), so this
would cause incorrect reports to show up.
This commit extends the cryptohash APIs so as callers of those routines
can fetch more context when an error happens, by using a new routine
called pg_cryptohash_error(). The error states are stored within each
implementation's internal context data, so as it is possible to extend
the logic depending on what's suited for an implementation. The default
implementation requires few error states, but OpenSSL could report
various issues depending on its internal state so more is needed in
cryptohash_openssl.c, and the code is shaped so as we are always able to
grab the necessary information.
The core code is changed to adapt to the new error routine, painting
more "const" across the call stack where the static errors are stored,
particularly in authentication code paths on variables that provide
log details. This way, any future changes would warn if attempting to
free these strings. The MD5 authentication code was also a bit blurry
about the handling of "logdetail" (LOG sent to the postmaster), so
improve the comments related that, while on it.
The origin of the problem is 87ae969, that introduced the centralized
cryptohash facility. Extra changes are done for pgcrypto in v14 for the
non-OpenSSL code path to cope with the improvements done by this
commit.
Reported-by: Michael Mühlbeyer
Author: Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/89B7F072-5BBE-4C92-903E-D83E865D9367@trivadis.com
Backpatch-through: 14
Prevent logical replication workers from performing insert, update,
delete, truncate, or copy commands on tables unless the subscription
owner has permission to do so.
Prevent subscription owners from circumventing row-level security by
forbidding replication into tables with row-level security policies
which the subscription owner is subject to, without regard to whether
the policy would ordinarily allow the INSERT, UPDATE, DELETE or
TRUNCATE which is being replicated. This seems sufficient for now, as
superusers, roles with bypassrls, and target table owners should still
be able to replicate despite RLS policies. We can revisit the
question of applying row-level security policies on a per-row basis if
this restriction proves too severe in practice.
Author: Mark Dilger
Reviewed-by: Jeff Davis, Andrew Dunstan, Ronan Dunklau
Discussion: https://postgr.es/m/9DFC88D3-1300-4DE8-ACBC-4CEF84399A53%40enterprisedb.com
get_rel_sync_entry(), which is called each time a change needs to be
logically replicated, is a rather hot code path in the WAL sender
sending logical changes. This code path was doing a relcache access on
relkind and relpartition for each logical change, but we only need to
know this information when building or re-building the cached
information for a relation.
Some measurements prove that this is noticeable in perf profiles,
particularly when attempting to replicate changes from relations that
are not published as these cause less overhead in the WAL sender,
delaying further the replication of changes for relations that are
published.
Issue introduced in 83fd453.
Author: Hou Zhijie
Reviewed-by: Kyotaro Horiguchi, Euler Taveira
Discussion: https://postgr.es/m/OS0PR01MB5716E863AA9E591C1F010F7A947D9@OS0PR01MB5716.jpnprd01.prod.outlook.com
Backpatch-through: 13
This commit adds a new system view pg_stat_subscription_workers, that
shows information about any errors which occur during the application of
logical replication changes as well as during performing initial table
synchronization. The subscription statistics entries are removed when the
corresponding subscription is removed.
It also adds an SQL function pg_stat_reset_subscription_worker() to reset
single subscription errors.
The contents of this view can be used by an upcoming patch that skips the
particular transaction that conflicts with the existing data on the
subscriber.
This view can be extended in the future to track other xact related
statistics like the number of xacts committed/aborted for subscription
workers.
Author: Masahiko Sawada
Reviewed-by: Greg Nancarrow, Hou Zhijie, Tang Haiying, Vignesh C, Dilip Kumar, Takamichi Osumi, Amit Kapila
Discussion: https://postgr.es/m/CAD21AoDeScrsHhLyEPYqN3sydg6PxAPVBboK=30xJfUVihNZDA@mail.gmail.com
Same macro names for SnapBuildOnDiskNotChecksummedSize and
SnapBuildOnDiskChecksummedSize are being used in slot.c and snapbuild.c.
This patch renames them, in slot.c, to
ReplicationSlotOnDiskNotChecksummedSize and
ReplicationSlotOnDiskChecksummedSize similar to the other macros. This
makes all macro names look consistent in slot.c.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACVZo-piDGzBOJRY4ob=_goFR6t9DhZMDMjJWN7LQs34Aw@mail.gmail.com
A couple of spots can benefit from an added errdetail(), which matches
what we were already doing in other places; and those that cannot
withstand errdetail() can get a more descriptive primary message.
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/CALj2ACV+cX1eM03GfcA=ZMLXh5fSn1X1auJLz3yuS1duPSb9QA@mail.gmail.com
protocol.sgml documented the layout for Type messages, but completely
dropped the ball otherwise, failing to explain what they are, when
they are sent, or what they're good for. While at it, do a little
copy-editing on the description of Relation messages.
In passing, adjust the comment for apply_handle_type() to make it
clearer that we choose not to do anything when receiving a Type
message, not that we think it has no use whatsoever.
Per question from Stefen Hillman.
Discussion: https://postgr.es/m/CAPgW8pMknK5pup6=T4a_UG=Cz80Rgp=KONqJmTdHfaZb0RvnFg@mail.gmail.com
Commit 5a1007a508 tried to introduce
an assertion that the block size was at least twice the size of a
tar block, but I got the math wrong. My error was reported to me
off-list.
A couple of code paths related to logical decoding (WAL sender, slot
advancing, etc.) use XLogReadRecord(), feeding on error messages
generated by walreader.c on a failure. All those messages have no
context, making it harder to spot from where an error could come even if
these should not happen. All the other callers of XLogReadRecord() do
that already.
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/YYnTH6OyOwQcAdkw@paquier.xyz
Earlier versions of PostgreSQL featured a version of pg_basebackup
that wanted to edit tar archives but was too dumb to parse them
properly. The server made things easier for the client by failing
to add the two blocks of zero bytes that ought to end a tar file,
leaving it up to the client to do that.
But since commit 23a1c6578c, we
don't need this hack any more, because pg_basebackup is now smarter
and can parse tar files even if they are properly terminated! So
change the server to always properly terminate the tar files. Older
versions of pg_basebackup can't talk to new servers anyway, so
there's no compatibility break.
On the pg_basebackup side, we see still need to add the terminating
zero bytes if we're talking to an older server, but not when the
server is v15+. Hopefully at some point we'll be able to remove
some of this compatibility cruft, but it seems best to hang on to
it for now.
In passing, add a file header comment to bbstreamer_tar.c, to make
it clearer what's going on here.
Discussion: http://postgr.es/m/CA+TgmoZbNzsWwM4BE5Jb_qHncY817DYZwGf+2-7hkMQ27ZwsMQ@mail.gmail.com
All such code deals with this global variable in one of three ways.
Sometimes the same functions use it in more than one of these ways
at the same time.
First, sometimes it's an implicit argument to one or more functions
being called in xlog.c or elsewhere, and must be set to the
appropriate value before calling those functions lest they
misbehave. In those cases, it is now passed as an explicit argument
instead.
Second, sometimes it's used to obtain the current timeline after
the end of recovery, i.e. the timeline to which WAL is being
written and flushed. Such code now calls GetWALInsertionTimeLine()
or relies on the new out parameter added to GetFlushRecPtr().
Third, sometimes it's used during recovery to store the current
replay timeline. That can change, so such code must generally
update the value before each use. It can still do that, but must
now use a local variable instead.
The net effect of these changes is to reduce by a fair amount the
amount of code that is directly accessing this global variable.
That's good, because history has shown that we don't always think
clearly about which timeline ID it's supposed to contain at any
given point in time, or indeed, whether it has been or needs to
be initialized at any given point in the code.
Patch by me, reviewed and tested by Michael Paquier, Amul Sul, and
Álvaro Herrera.
Discussion: https://postgr.es/m/CA+TgmobfAAqhfWa1kaFBBFvX+5CjM=7TE=n4r4Q1o2bjbGYBpA@mail.gmail.com
In slotfuncs.c, pg_replication_slot_advance() needs to determine
the LSN up to which the slot should be advanced, but that doesn't
require us to update ThisTimeLineID, because none of the code called
from here depends on it. If the replication slot is logical,
pg_logical_replication_slot_advance will call read_local_xlog_page,
which does use ThisTimeLineID, but also takes care of making sure
it's up to date. If the replication slot is physical, the timeline
isn't used for anything at all.
In logicalfuncs.c, pg_logical_slot_get_changes_guts() has the same
issue: the only code we're going to run that cares about timelines
is in or downstream of read_local_xlog_page, which already makes
sure that the correct value gets set. Hence, don't do it here.
Patch by me, reviewed and tested by Michael Paquier, Amul Sul, and
Álvaro Herrera.
Discussion: https://postgr.es/m/CA+TgmobfAAqhfWa1kaFBBFvX+5CjM=7TE=n4r4Q1o2bjbGYBpA@mail.gmail.com
The base backup code has accumulated a healthy number of new
features over the years, but it's becoming increasingly difficult
to maintain and further enhance that code because there's no
real separation of concerns. For example, the code that
understands knows the details of how we send data to the client
using the libpq protocol is scattered throughout basebackup.c,
rather than being centralized in one place.
To try to improve this situation, introduce a new 'bbsink' object
which acts as a recipient for archives generated during the base
backup progress and also for the backup manifest. This commit
introduces three types of bbsink: a 'copytblspc' bbsink forwards the
backup to the client using one COPY OUT operation per tablespace and
another for the manifest, a 'progress' bbsink performs command
progress reporting, and a 'throttle' bbsink performs rate-limiting.
The 'progress' and 'throttle' bbsink types also forward the data to a
successor bbsink; at present, the last bbsink in the chain will
always be of type 'copytblspc'. There are plans to add more types
of 'bbsink' in future commits.
This abstraction is a bit leaky in the case of progress reporting,
but this still seems cleaner than what we had before.
Patch by me, reviewed and tested by Andres Freund, Sumanta Mukherjee,
Dilip Kumar, Suraj Kharage, Dipesh Pandit, Tushar Ahuja, Mark Dilger,
and Jeevan Ladhe.
Discussion: https://postgr.es/m/CA+TgmoZGwR=ZVWFeecncubEyPdwghnvfkkdBe9BLccLSiqdf9Q@mail.gmail.com
Discussion: https://postgr.es/m/CA+TgmoZvqk7UuzxsX1xjJRmMGkqoUGYTZLDCH8SmU1xTPr1Xig@mail.gmail.com
In walreceiver, set the publisher's relevant GUCs (datestyle,
intervalstyle, extra_float_digits) to the same values that pg_dump uses,
and for the same reason: we need the output to be read the same way
regardless of the receiver's settings. Without this, it's possible
for subscribers to misinterpret transmitted values.
Although this is clearly a bug fix, it's not without downsides:
subscribers that are storing values into some other datatype, such as
text, could get different results than before, and perhaps be unhappy
about that. Given the lack of previous complaints, it seems best
to change this only in HEAD, and to call it out as an incompatible
change in v15.
Japin Li, per report from Sadhuprasad Patro
Discussion: https://postgr.es/m/CAFF0-CF=D7pc6st-3A9f1JnOt0qmc+BcBPVzD6fLYisKyAjkGA@mail.gmail.com
Failing to do so results in inability of logical decoding to process the
WAL stream. Handle it by doing nothing.
Backpatch all the way back.
Reported-by: Petr Jelínek <petr.jelinek@enterprisedb.com>
The previous code used ThisTimeLineID, which need not even be
initialized here, although it usually was in practice, because
pg_basebackup issues IDENTIFY_SYSTEM before calling BASE_BACKUP,
and that initializes ThisTimeLineID as a side effect. That's not
really good enough, though, not only because we shoudn't be counting
on side effects like that, but also because the TLI could change
meanwhile. Fortunately, we have convenient access to more meaningful
TLI values, so use those instead.
Because of the way this logic is coded, the consequences of using
a possibly-incorrect TLI here are no worse than a slightly confusing
error message, I don't want to take any risk here, so no back-patch
at least for now.
Patch by me, reviewed by Kyotaro Horiguchi and Michael Paquier
Discussion: http://postgr.es/m/CA+TgmoZRNWGWYDX9RgTXMG6_nwSdB=PB-PPRUbvMUTGfmL2sHQ@mail.gmail.com
A new option "FOR ALL TABLES IN SCHEMA" in Create/Alter Publication allows
one or more schemas to be specified, whose tables are selected by the
publisher for sending the data to the subscriber.
The new syntax allows specifying both the tables and schemas. For example:
CREATE PUBLICATION pub1 FOR TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;
OR
ALTER PUBLICATION pub1 ADD TABLE t1,t2,t3, ALL TABLES IN SCHEMA s1,s2;
A new system table "pg_publication_namespace" has been added, to maintain
the schemas that the user wants to publish through the publication.
Modified the output plugin (pgoutput) to publish the changes if the
relation is part of schema publication.
Updates pg_dump to identify and dump schema publications. Updates the \d
family of commands to display schema publications and \dRp+ variant will
now display associated schemas if any.
Author: Vignesh C, Hou Zhijie, Amit Kapila
Syntax-Suggested-by: Tom Lane, Alvaro Herrera
Reviewed-by: Greg Nancarrow, Masahiko Sawada, Hou Zhijie, Amit Kapila, Haiying Tang, Ajin Cherian, Rahila Syed, Bharath Rupireddy, Mark Dilger
Tested-by: Haiying Tang
Discussion: https://www.postgresql.org/message-id/CALDaNm0OANxuJ6RXqwZsM1MSY4s19nuH3734j4a72etDwvBETQ@mail.gmail.com
According to the comments, we initialize sendTimeLineIsHistoric
and sendTimeLine here for the benefit of WalSndSegmentOpen.
However, the only way that can happen is if logical_read_xlog_page
calls WALRead. And since logical_read_xlog_page initializes the
same global variables internally, we don't need to also do it here.
These initializations have been here since replication slots were
introduced in commit 858ec11858. They
were certainly useless at that time, too, because logical decoding
didn't yet exist then, and physical replication doesn't examine any
WAL at the time of slot creation. I haven't checked all the
intermediate versions, but I suspect there's no point at which
this code ever did anything useful.
To reduce future confusion, remove the code. Since there's no
functional defect, no back-patch.
Discussion: http://postgr.es/m/CA+TgmobSWzacEs+r6C-7DrOPDHoDar4i9gzxB3SCBr5qjnLmVQ@mail.gmail.com
The command is supported for physical slots for now, and returns the
type of slot, its restart_lsn and its restart_tli.
This will be useful for an upcoming patch related to pg_receivewal, to
allow the tool to be able to stream from the position of a slot, rather
than the last WAL position flushed by the backend (as reported by
IDENTIFY_SYSTEM) if the archive directory is found as empty, which would
be an advantage in the case of switching to a different archive
locations with the same slot used to avoid holes in WAL segment
archives.
Author: Ronan Dunklau
Reviewed-by: Kyotaro Horiguchi, Michael Paquier, Bharath Rupireddy
Discussion: https://postgr.es/m/18708360.4lzOvYHigE@aivenronan
During a replication slot creation, an ERROR generated in the same
transaction as the one creating a to-be-exported snapshot would have
left the backend in an inconsistent state, as the associated static
export snapshot state was not being reset on transaction abort, but only
on the follow-up command received by the WAL sender that created this
snapshot on replication slot creation. This would trigger inconsistency
failures if this session tried to export again a snapshot, like during
the creation of a replication slot.
Note that a snapshot export cannot happen in a transaction block, so
there is no need to worry resetting this state for subtransaction
aborts. Also, this inconsistent state would very unlikely show up to
users. For example, one case where this could happen is an
out-of-memory error when building the initial snapshot to-be-exported.
Dilip found this problem while poking at a different patch, that caused
an error in this code path for reasons unrelated to HEAD.
Author: Dilip Kumar
Reviewed-by: Michael Paquier, Zhihong Yu
Discussion: https://postgr.es/m/CAFiTN-s0zA1Kj0ozGHwkYkHwa5U0zUE94RSc_g81WrpcETB5=w@mail.gmail.com
Backpatch-through: 9.6
Sometimes, we replace a symbolic link that we find in the data
directory with an actual directory within the tarfile that we
create. _tarWriteDir was responsible both for making this
substitution and also for writing the tar header for the
resulting directory into the tar file. Make it do only the first
of those things, and rename to convert_link_to_directory.
Substantially larger refactoring of this source file is planned,
but this little bit seemed to make sense to commit
independently.
Discussion: http://postgr.es/m/CA+Tgmobz6tuv5tr-WxURe5JA1vVcGz85k4kkvoWxcyHvDpEqFA@mail.gmail.com
Like BASE_BACKUP, CREATE_REPLICATION_SLOT has historically used a
hard-coded syntax. To improve future extensibility, adopt a flexible
options syntax here, too.
In the new syntax, instead of three mutually exclusive options
EXPORT_SNAPSHOT, USE_SNAPSHOT, and NOEXPORT_SNAPSHOT, there is now a single
SNAPSHOT option with three possible values: 'export', 'use', and 'nothing'.
This commit does not remove support for the old syntax. It just adds
the new one as an additional option, makes pg_receivewal,
pg_recvlogical, and walreceiver processes use it.
Patch by me, reviewed by Fabien Coelho, Sergei Kornilov, and
Fujii Masao.
Discussion: http://postgr.es/m/CA+TgmobAczXDRO_Gr2euo_TxgzaH1JxbNxvFx=HYvBinefNH8Q@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoZGwR=ZVWFeecncubEyPdwghnvfkkdBe9BLccLSiqdf9Q@mail.gmail.com
Previously, BASE_BACKUP used an entirely hard-coded syntax, but that's
hard to extend. Instead, adopt the same kind of syntax we've used for
SQL commands such as VACUUM, ANALYZE, COPY, and EXPLAIN, where it's
not necessary for all of the option names to be parser keywords.
In the new syntax, most of the options now take an optional Boolean
argument. To match our practice in other in places, the options which
the old syntax called NOWAIT and NOVERIFY_CHECKSUMS options are in the
new syntax called WAIT and VERIFY_CHECKUMS, and the default value is
false. In the new syntax, the FAST option has been replaced by a
CHECKSUM option whose value may be 'fast' or 'spread'.
This commit does not remove support for the old syntax. It just adds
the new one as an additional option, and makes pg_basebackup prefer
the new syntax when the server is new enough to support it.
Patch by me, reviewed and tested by Fabien Coelho, Sergei Kornilov,
Fujii Masao, and Tushar Ahuja.
Discussion: http://postgr.es/m/CA+TgmobAczXDRO_Gr2euo_TxgzaH1JxbNxvFx=HYvBinefNH8Q@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmoZGwR=ZVWFeecncubEyPdwghnvfkkdBe9BLccLSiqdf9Q@mail.gmail.com
Two functions, both named check_permissions(), used the same checks to
verify if a user had required privileges to work on replication slots.
This commit removes the duplication, and moves the function doing the
checks to slot.c to be centralized.
Author: Bharath Rupireddy
Reviewed-by: Nathan Bossart, Euler Taveira
Discussion: https://postgr.es/m/CALj2ACUPpVw1u7sQocFVWrSs0n10pt_G_4NPZKSxXK6cW1dErw@mail.gmail.com
While processing toast changes in logical decoding, we rejigger the
tuple change to point to in-memory toast tuples instead to on-disk toast
tuples. And, to make sure the memory accounting is correct, we were
subtracting the old change size and then after re-computing the new tuple,
re-adding its size at the end. Now, if there is any error before we add
the new size, we will release the changes and that will update the
accounting info (subtracting the size from the counters). And we were
underflowing there which leads to an assertion failure in assert enabled
builds and wrong memory accounting in reorder buffer otherwise.
Author: Bertrand Drouvot
Reviewed-by: Amit Kapila
Backpatch-through: 13, where memory accounting was introduced
Discussion: https://postgr.es/m/92b0ee65-b8bd-e42d-c082-4f3f4bf12d34@amazon.com
Previously, walreceiver always closed the currently-opened WAL segment
and created its archive notification file, after it finished writing
the current segment up and received any WAL data that should be
written into the next segment. If walreceiver exited just before
any WAL data in the next segment arrived at standby, it did not
create the archive notification file of the current segment
even though that's known completed. This behavior could cause
WAL archiving of the segment to be delayed until subsequent
restartpoints or checkpoints created its notification file.
To fix the issue, this commit changes walreceiver so that it creates
an archive notification file of a current WAL segment immediately
if that's known completed before receiving next WAL data.
Back-patch to all supported branches.
Reported-by: Kyotaro Horiguchi
Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20200630.165503.1465894182551545886.horikyota.ntt@gmail.com
Similar to LogicalIncreaseRestartDecodingForSlot() add a debug message to
LogicalIncreaseXminForSlot() reporting a new catalog_xmin candidate.
This just adds additional diagnostic information during logical decoding that
can aid debugging.
Author: Ashutosh Bapat
Reviewed-by: Masahiko Sawada, Amit Kapila
Discussion: https://postgr.es/m/CAExHW5usQWbiUz0hHOCu5twS1O9DvpcPojf6sor=8q--VUuMbA@mail.gmail.com
Use one fileset for the entire worker lifetime instead of using
separate filesets for each streaming transaction. Now, the
changes/subxacts files for every streaming transaction will be
created under the same fileset and the files will be deleted
after the transaction is completed.
This patch extends the BufFileOpenFileSet and BufFileDeleteFileSet
APIs to allow users to specify whether to give an error on missing
files.
Author: Dilip Kumar, based on suggestion by Thomas Munro
Reviewed-by: Hou Zhijie, Masahiko Sawada, Amit Kapila
Discussion: https://postgr.es/m/E1mCC6U-0004Ik-Fs@gemulon.postgresql.org
Move fileset related implementation out of sharedfileset.c to allow its
usage by backends that don't want to share filesets among different
processes. After this split, fileset infrastructure is used by both
sharedfileset.c and worker.c for the named temporary files that survive
across transactions.
Author: Dilip Kumar, based on suggestion by Andres Freund
Reviewed-by: Hou Zhijie, Masahiko Sawada, Amit Kapila
Discussion: https://postgr.es/m/E1mCC6U-0004Ik-Fs@gemulon.postgresql.org
Previously, on the subscriber, we set the error context callback for the
tuple data conversion failures. This commit replaces the existing error
context callback with a comprehensive one so that it shows not only the
details of data conversion failures but also the details of logical change
being applied by the apply worker or table sync worker. The additional
information displayed will be the command, transaction id, and timestamp.
The error context is added to an error only when applying a change but not
while doing other work like receiving data etc.
This will help users in diagnosing the problems that occur during logical
replication. It also can be used for future work that allows skipping a
particular transaction on the subscriber.
Author: Masahiko Sawada
Reviewed-by: Hou Zhijie, Greg Nancarrow, Haiying Tang, Amit Kapila
Tested-by: Haiying Tang
Discussion: https://postgr.es/m/CAD21AoDeScrsHhLyEPYqN3sydg6PxAPVBboK=30xJfUVihNZDA@mail.gmail.com
WAL records may span multiple segments, but XLogWrite() does not
wait for the entire record to be written out to disk before
creating archive status files. Instead, as soon as the last WAL page of
the segment is written, the archive status file is created, and the
archiver may process it. If PostgreSQL crashes before it is able to
write and flush the rest of the record (in the next WAL segment), the
wrong version of the first segment file lingers in the archive, which
causes operations such as point-in-time restores to fail.
To fix this, keep track of records that span across segments and ensure
that segments are only marked ready-for-archival once such records have
been completely written to disk.
This has always been wrong, so backpatch all the way back.
Author: Nathan Bossart <bossartn@amazon.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Ryo Matsumura <matsumura.ryo@fujitsu.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/CBDDFA01-6E40-46BB-9F98-9340F4379505@amazon.com
In a backup manifest, WAL-Ranges stores the range of WAL that is
required for the backup to be valid. pg_verifybackup would then
internally use pg_waldump for the checks based on this data.
When the timeline where the backup started was more than 1 with a
history file looked at for the manifest data generation, the calculation
of the WAL range for the first timeline to check was incorrect. The
previous logic used as start LSN the start position of the first
timeline, but it needs to use the start LSN of the backup. This would
cause failures with pg_verifybackup, or any tools making use of the
backup manifests.
This commit adds a test based on a logic using a self-promoted node,
making it rather cheap.
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20210818.143031.1867083699202617521.horikyota.ntt@gmail.com
Backpatch-through: 13
In the code, most places used the term "Stream Stop" for the logical
stream message. This commit improves consistency by renaming LogicalRepMsgType
"LOGICAL_REP_MSG_STREAM_END" to "LOGICAL_REP_MSG_STREAM_STOP".
Author: Masahiko Sawada
Reviewed-by: Hou Zhijie, Amit Kapila
Discussion: https://postgr.es/m/CAD21AoDeScrsHhLyEPYqN3sydg6PxAPVBboK=30xJfUVihNZDA@mail.gmail.com
This is a combined revert of the following commits:
- c3826f8, a refactoring piece that moved the hex decoding code to
src/common/. This code was cleaned up by aef8948, as it originally
included no overflow checks in the same way as the base64 routines in
src/common/ used by SCRAM, making it unsafe for its purpose.
- aef8948, a more advanced refactoring of the hex encoding/decoding code
to src/common/ that added sanity checks on the result buffer for hex
decoding and encoding. As reported by Hans Buschmann, those overflow
checks are expensive, and it is possible to see a performance drop in
the decoding/encoding of bytea or LOs the longer they are. Simple SQLs
working on large bytea values show a clear difference in perf profile.
- ccf4e27, a cleanup made possible by aef8948.
The reverts of all those commits bring back the performance of hex
decoding and encoding back to what it was in ~13. Fow now and
post-beta3, this is the simplest option.
Reported-by: Hans Buschmann
Discussion: https://postgr.es/m/1629039545467.80333@nidsa.net
Backpatch-through: 14
Commit a8fd13cab0 added support for prepared transactions to built-in
logical replication via a new option "two_phase" for a subscription. The
"two_phase" option was not allowed with the existing streaming option.
This commit permits the combination of "streaming" and "two_phase"
subscription options. It extends the pgoutput plugin and the subscriber
side code to add the prepare API for streaming transactions which will
apply the changes accumulated in the spool-file at prepare time.
Author: Peter Smith and Ajin Cherian
Reviewed-by: Vignesh C, Amit Kapila, Greg Nancarrow
Tested-By: Haiying Tang
Discussion: https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ru
Discussion: https://postgr.es/m/CAMGcDxeqEpWj3fTXwqhSwBdXd2RS9jzwWscO-XbeCfso6ts3+Q@mail.gmail.com
This is a non-functional change only to refactor code to extract some
replication logic into static functions.
This is done as preparation for the 2PC streaming patch which also shares
this common logic.
Author: Peter Smith
Reviewed-By: Amit Kapila
Discussion: https://postgr.es/m/CAHut+PuiSA8AiLcE2N5StzSKs46SQEP_vDOUD5fX2XCVtfZ7mQ@mail.gmail.com
When some slots are invalidated due to the max_slot_wal_keep_size limit,
the old segment horizon should move forward to stay within the limit.
However, in commit c655077639 we forgot to call KeepLogSeg again to
recompute the horizon after invalidating replication slots. In cases
where other slots remained, the limits would be recomputed eventually
for other reasons, but if all slots were invalidated, the limits would
not move at all afterwards. Repair.
Backpatch to 13 where the feature was introduced.
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reported-by: Marcin Krupowicz <mk@071.ovh>
Discussion: https://postgr.es/m/17103-004130e8f27782c9@postgresql.org
To add support for streaming transactions at prepare time into the
built-in logical replication, we need to do the following things:
* Modify the output plugin (pgoutput) to implement the new two-phase API
callbacks, by leveraging the extended replication protocol.
* Modify the replication apply worker, to properly handle two-phase
transactions by replaying them on prepare.
* Add a new SUBSCRIPTION option "two_phase" to allow users to enable
two-phase transactions. We enable the two_phase once the initial data sync
is over.
We however must explicitly disable replication of two-phase transactions
during replication slot creation, even if the plugin supports it. We
don't need to replicate the changes accumulated during this phase,
and moreover, we don't have a replication connection open so we don't know
where to send the data anyway.
The streaming option is not allowed with this new two_phase option. This
can be done as a separate patch.
We don't allow to toggle two_phase option of a subscription because it can
lead to an inconsistent replica. For the same reason, we don't allow to
refresh the publication once the two_phase is enabled for a subscription
unless copy_data option is false.
Author: Peter Smith, Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Sawada Masahiko, Vignesh C, Dilip Kumar, Takamichi Osumi, Greg Nancarrow
Tested-By: Haiying Tang
Discussion: https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ru
Discussion: https://postgr.es/m/CAA4eK1+opiV4aFTmWWUF9h_32=HfPOW9vZASHarT0UA5oBrtGw@mail.gmail.com
The requirement that IDENTIFY_SYSTEM be run before START_REPLICATION
was both undocumented and unnecessary. Remove the error and ensure
that ThisTimeLineID is initialized in START_REPLICATION.
Elect not to backport because this requirement was expected behavior
(even if inconsistently enforced), and is not likely to cause any
major problem.
Author: Jeff Davis
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/de4bbf05b7cd94227841c433ea6ff71d2130c713.camel%40j-davis.com
The existing code tried to do syscache lookups in an already-failed
transaction, which is problematic to say the least. After some
consideration of alternatives, the best fix seems to be to just drop
type names from the error message altogether. The table and column
names seem like sufficient localization. If the user is unsure what
types are involved, she can check the local and remote table
definitions.
Having done that, we can also discard the LogicalRepTypMap hash
table, which had no other use. Arguably, LOGICAL_REP_MSG_TYPE
replication messages are now obsolete as well; but we should
probably keep them in case some other use emerges. (The complexity
of removing something from the replication protocol would likely
outweigh any savings anyhow.)
Masahiko Sawada and Bharath Rupireddy, per complaint from Andres
Freund. Back-patch to v10 where this code originated.
Discussion: https://postgr.es/m/20210106020229.ne5xnuu6wlondjpe@alap3.anarazel.de
Until now, we didn't allow to stream the changes in logical replication
till we receive speculative confirm or the next DML change record after
speculative inserts. The reason was that we never use to process
speculative aborts but after commit 4daa140a2f it is possible to process
them so we can allow streaming once we receive speculative abort after
speculative insertion.
We decided to backpatch to 14 where the feature for streaming in progress
transactions have been introduced as this is a minor change and makes that
functionality better.
Author: Amit Kapila
Reviewed-By: Dilip Kumar
Backpatch-through: 14
Discussion: https://postgr.es/m/CAA4eK1KdqmTCtrBR6oFfGELrLLbDLDedL6zACcsUOQuTJBj1vw@mail.gmail.com
Extend the replication command CREATE_REPLICATION_SLOT to support the
TWO_PHASE option. This will allow decoding commands like PREPARE
TRANSACTION, COMMIT PREPARED and ROLLBACK PREPARED for slots created with
this option. The decoding of the transaction happens at prepare command.
This patch also adds support of two-phase in pg_recvlogical via a new
option --two-phase.
This option will also be used by future patches that allow streaming of
transactions at prepare time for built-in logical replication. With this,
the out-of-core logical replication solutions can enable replication of
two-phase transactions via replication protocol.
Author: Ajin Cherian
Reviewed-By: Jeff Davis, Vignesh C, Amit Kapila
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/64b9f783c6e125f18f88fbc0c0234e34e71d8639.camel@j-davis.com
Before a restartpoint finishes PreallocXlogFiles(), a startup process
KeepFileRestoredFromArchive() call can unlink the preallocated segment.
If a CHECKPOINT sql command had elicited the restartpoint experiencing
the race condition, that sql command failed. Moreover, the restartpoint
omitted its log_checkpoints message and some inessential resource
reclamation. Prevent the ERROR by skipping open() of the segment.
Since these consequences are so minor, no back-patch.
Discussion: https://postgr.es/m/20210202151416.GB3304930@rfd.leadboat.com
Only initdb used it. initdb refuses to operate on a non-empty directory
and generally does not cope with pre-existing files of other kinds.
Hence, use the opportunity to simplify.
Discussion: https://postgr.es/m/20210202151416.GB3304930@rfd.leadboat.com
I started out with the goal of reporting ERRCODE_CONNECTION_FAILURE
when walrcv_connect() fails, but as I looked around I realized that
whoever wrote this code was of the opinion that errcodes are purely
optional. That's not my understanding of our project policy. Hence,
make sure that an errcode is provided in each ereport that (a) is
ERROR or higher level and (b) isn't arguably an internal logic error.
Also fix some very dubious existing errcode assignments.
While this is not per policy, it's also largely cosmetic, since few
of these cases could get reported to applications. So I don't
feel a need to back-patch.
Discussion: https://postgr.es/m/2189704.1623512522@sss.pgh.pa.us
During decoding for speculative inserts, we were relying for cleaning
toast hash on confirmation records or next change records. But that
could lead to multiple problems (a) memory leak if there is neither a
confirmation record nor any other record after toast insertion for a
speculative insert in the transaction, (b) error and assertion failures
if the next operation is not an insert/update on the same table.
The fix is to start queuing spec abort change and clean up toast hash
and change record during its processing. Currently, we are queuing the
spec aborts for both toast and main table even though we perform cleanup
while processing the main table's spec abort record. Later, if we have a
way to distinguish between the spec abort record of toast and the main
table, we can avoid queuing the change for spec aborts of toast tables.
Reported-by: Ashutosh Bapat
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Backpatch-through: 9.6, where it was introduced
Discussion: https://postgr.es/m/CAExHW5sPKF-Oovx_qZe4p5oM6Dvof7_P+XgsNAViug15Fm99jA@mail.gmail.com
I overlooked that one condition was logically inverted. The fix is a
little bit more involved than simply negating the condition, to make
the code easier to read.
Fix some outdated comments left by the same commit, while at it.
Author: Masahiko Sawada <sawada.mshk@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/YMRlmB3/lZw8YBH+@paquier.xyz
Using an Assert to check the validity of incoming messages is an
extremely poor decision. In a debug build, it should not be that easy
for a broken or malicious remote client to crash the logrep worker.
The consequences could be even worse in non-debug builds, which will
fail to make such checks at all, leading to who-knows-what misbehavior.
Hence, promote every Assert that could possibly be triggered by wrong
or out-of-order replication messages to a full test-and-ereport.
To avoid bloating the set of messages the translation team has to cope
with, establish a policy that replication protocol violation error
reports don't need to be translated. Hence, all the new messages here
use errmsg_internal(). A couple of old messages are changed likewise
for consistency.
Along the way, fix some non-idiomatic or outright wrong uses of
hash_search().
Most of these mistakes are new with the "streaming replication"
patch (commit 464824323), but a couple go back a long way.
Back-patch as appropriate.
Discussion: https://postgr.es/m/1719083.1623351052@sss.pgh.pa.us
apply_handle_tuple_routing(), having detected and reported that
the tuple it needed to update didn't exist, tried to update that
tuple anyway, leading to a null-pointer dereference.
logicalrep_partition_open() failed to ensure that the
LogicalRepPartMapEntry it built for a partition was fully
independent of that for the partition root, leading to
trouble if the root entry was later freed or rebuilt.
Meanwhile, on the publisher's side, pgoutput_change() sometimes
attempted to apply execute_attr_map_tuple() to a NULL tuple.
The first of these was reported by Sergey Bernikov in bug #17055;
I found the other two while developing some test cases for this
sadly under-tested code.
Diagnosis and patch for the first issue by Amit Langote; patches
for the others by me; new test cases by me. Back-patch to v13
where this logic came in.
Discussion: https://postgr.es/m/17055-9ba800ec8522668b@postgresql.org
The code added to mark replication slots invalid in commit c655077639
had the race condition that a slot can be dropped or advanced
concurrently with checkpointer trying to invalidate it. Rewrite the
code to close those races.
The changes to ReplicationSlotAcquire's API added with c655077639 are
not necessary anymore. To avoid an ABI break in released branches, this
commit leaves that unchanged; it'll be changed in a master-only commit
separately.
Backpatch to 13, where this code first appeared.
Reported-by: Andres Freund <andres@anarazel.de>
Author: Andres Freund <andres@anarazel.de>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20210408001037.wfmk6jud36auhfqm@alap3.anarazel.de
It turns out that worker.c's code path for TRUNCATE was also
careless about establishing a snapshot while executing user-defined
code, allowing the checks added by commit 84f5c2908 to fail when
a trigger is fired in that context.
We could just wrap Push/PopActiveSnapshot around the truncate call,
but it seems better to establish a policy of holding a snapshot
throughout execution of a replication step. To help with that and
possible future requirements, replace the previous ensure_transaction
calls with pairs of begin/end_replication_step calls.
Per report from Mark Dilger. Back-patch to v11, like the previous
changes.
Discussion: https://postgr.es/m/B4A3AF82-79ED-4F4C-A4E5-CD2622098972@enterprisedb.com
Commit 19890a064e added the option to enable two_phase commits via
pg_create_logical_replication_slot but didn't extend the support of same
in replication protocol. However, by mistake, it added the two_phase
variable in CreateReplicationSlotCmd which is required only when we extend
the replication protocol.
Reported-by: Jeff Davis
Author: Ajin Cherian
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/64b9f783c6e125f18f88fbc0c0234e34e71d8639.camel@j-davis.com
Release memory allocated when creating the tuple-conversion map and its
component TupleDescs when its owning sync entry is invalidated.
TupleDescs must also be freed when no map is deemed necessary, to begin
with.
Reported-by: Andres Freund
Author: Amit Langote
Reviewed-by: Takamichi Osumi, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/MEYP282MB166933B1AB02B4FE56E82453B64D9@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
While decoding the multi-insert WAL we can't clean the toast untill we get
the last insert of that WAL record. Now if we stream the changes before we
get the last change, the memory for toast chunks won't be released and we
expect the txn to have streamed all changes after streaming. This
restriction is mainly to ensure the correctness of streamed transactions
and it doesn't seem worth uplifting such a restriction just to allow this
case because anyway we will stream the transaction once such an insert is
complete.
Previously we were using two different flags (one for toast tuples and
another for speculative inserts) to indicate partial changes. Now instead
we replaced both of them with a single flag to indicate partial changes.
Reported-by: Pavan Deolasee
Author: Dilip Kumar
Reviewed-by: Pavan Deolasee, Amit Kapila
Discussion: https://postgr.es/m/CABOikdN-_858zojYN-2tNcHiVTw-nhxPwoQS4quExeweQfG1Ug@mail.gmail.com
If we redirected a replicated tuple operation into a partition child
table, and then tried to fire AFTER triggers for that event, the
relation cache entry for the child table was already closed. This has
no visible ill effects as long as the entry is still there and still
valid, but an unluckily-timed cache flush could result in a crash or
other misbehavior.
To fix, postpone the ExecCleanupTupleRouting call (which is what
closes the child table) until after we've fired triggers. This
requires a bit of refactoring so that the cleanup function can
have access to the necessary state.
In HEAD, I took the opportunity to simplify some of worker.c's
function APIs based on use of the new ApplyExecutionData struct.
However, it doesn't seem safe/practical to back-patch that aspect,
at least not without a lot of analysis of possible interactions
with a04daa97a.
In passing, add an Assert to afterTriggerInvokeEvents to catch
such cases. This seems worthwhile because we've grown a number
of fairly unstructured ways of calling AfterTriggerEndQuery.
Back-patch to v13, where worker.c grew the ability to deal with
partitioned target tables.
Discussion: https://postgr.es/m/3382681.1621381328@sss.pgh.pa.us
COMMIT/ROLLBACK necessarily destroys all snapshots within the session.
The original implementation of intra-procedure transactions just
cavalierly did that, ignoring the fact that this left us executing in
a rather different environment than normal. In particular, it turns
out that handling of toasted datums depends rather critically on there
being an outer ActiveSnapshot: otherwise, when SPI or the core
executor pop whatever snapshot they used and return, it's unsafe to
dereference any toasted datums that may appear in the query result.
It's possible to demonstrate "no known snapshots" and "missing chunk
number N for toast value" errors as a result of this oversight.
Historically this outer snapshot has been held by the Portal code,
and that seems like a good plan to preserve. So add infrastructure
to pquery.c to allow re-establishing the Portal-owned snapshot if it's
not there anymore, and add enough bookkeeping support that we can tell
whether it is or not.
We can't, however, just re-establish the Portal snapshot as part of
COMMIT/ROLLBACK. As in normal transaction start, acquiring the first
snapshot should wait until after SET and LOCK commands. Hence, teach
spi.c about doing this at the right time. (Note that this patch
doesn't fix the problem for any PLs that try to run intra-procedure
transactions without using SPI to execute SQL commands.)
This makes SPI's no_snapshots parameter rather a misnomer, so in HEAD,
rename that to allow_nonatomic.
replication/logical/worker.c also needs some fixes, because it wasn't
careful to hold a snapshot open around AFTER trigger execution.
That code doesn't use a Portal, which I suspect someday we're gonna
have to fix. But for now, just rearrange the order of operations.
This includes back-patching the recent addition of finish_estate()
to centralize the cleanup logic there.
This also back-patches commit 2ecfeda3e into v13, to improve the
test coverage for worker.c (it was that test that exposed that
worker.c's snapshot management is wrong).
Per bug #15990 from Andreas Wicht. Back-patch to v11 where
intra-procedure COMMIT was added.
Discussion: https://postgr.es/m/15990-eee2ac466b11293d@postgresql.org
While applying the truncate change, the logical apply worker acquires
RowExclusiveLock on the relation being truncated. This allowed truncate on
the relation at a time by two apply workers which lead to a deadlock. The
reason was that one of the workers after updating the pg_class tuple tries
to acquire SHARE lock on the relation and started to wait for the second
worker which has acquired RowExclusiveLock on the relation. And when the
second worker tries to update the pg_class tuple, it starts to wait for
the first worker which leads to a deadlock. Fix it by acquiring
AccessExclusiveLock on the relation before applying the truncate change as
we do for normal truncate operation.
Author: Peter Smith, test case by Haiying Tang
Reviewed-by: Dilip Kumar, Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/CAHut+PsNm43p0jM+idTvWwiGZPcP0hGrHMPK9TOAkc+a4UpUqw@mail.gmail.com
The worker.c global wrconn is only meant to be used by logical apply/
tablesync workers, but there are other variables with the same name. To
reduce future confusion rename the global from "wrconn" to
"LogRepWorkerWalRcvConn".
While this is just cosmetic, it seems better to backpatch it all the way
back to 10 where this code appeared, to avoid future backpatching
issues.
Author: Peter Smith <smithpb2250@gmail.com>
Discussion: https://postgr.es/m/CAHut+Pu7Jv9L2BOEx_Z0UtJxfDevQSAUW2mJqWU+CtmDrEZVAg@mail.gmail.com
Also "make reformat-dat-files".
The only change worthy of note is that pgindent messed up the formatting
of launcher.c's struct LogicalRepWorkerId, which led me to notice that
that struct wasn't used at all anymore, so I just took it out.
This set of commits has some bugs with known fixes, but at this late
stage in the release cycle it seems best to revert and resubmit next
time, along with some new automated test coverage for this whole area.
Commits reverted:
dc88460c: Doc: Review for "Optionally prefetch referenced data in recovery."
1d257577: Optionally prefetch referenced data in recovery.
f003d9f8: Add circular WAL decoding buffer.
323cbe7c: Remove read_page callback from XLogReader.
Remove the new GUC group WAL_RECOVERY recently added by a55a9847, as the
corresponding section of config.sgml is now reverted.
Discussion: https://postgr.es/m/CAOuzzgrn7iKnFRsB4MHp3UisEQAGgZMbk_ViTN4HV4-Ksq8zCg%40mail.gmail.com
Currently, replication slot statistics are updated at prepare, commit, and
rollback. Now, if the transaction is interrupted the stats might not get
updated. Fixed this by updating replication statistics after every
stream/spill.
In passing update the docs to change the description of some of the slot
stats.
Author: Vignesh C, Sawada Masahiko
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
During decoding of an in-progress or prepared transaction, we detect
concurrent abort with an error code ERRCODE_TRANSACTION_ROLLBACK. That is
not sufficient because a callback can decide to throw that error code
at other times as well.
Reported-by: Tom Lane
Author: Amit Kapila
Reviewed-by: Dilip Kumar
Discussion: https://postgr.es/m/CAA4eK1KCjPRS4aZHB48QMM4J8XOC1+TD8jo-4Yu84E+MjwqVhA@mail.gmail.com
Previously, we were using the size of all the changes present in
ReorderBuffer to compute total_bytes after decoding a transaction and that
can lead to counting some of the transactions' changes more than once. Fix
it by using the size of the changes decoded for a transaction to compute
'total_bytes'.
Author: Sawada Masahiko
Reviewed-by: Vignesh C, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
There were two problems:
a. We were always selecting the next available txn instead of selecting it
when it is larger than the previous transaction.
b. We were selecting the transactions which haven't made any changes to
the database (base snapshot is not set). Later it was hitting an Assert
because we don't decode such transactions and the changes in txn remain as
it is. It is better not to choose such transactions for streaming in the
first place.
Reported-by: Haiying Tang
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/OS0PR01MB61133B94E63177040F7ECDA1FB429@OS0PR01MB6113.jpnprd01.prod.outlook.com
We had a report of confusing server behavior caused by a client bug
that sent junk to the server: the server thought the junk was a
very long message length and waited patiently for data that would
never come. We can reduce the risk of that by being less trusting
about message lengths.
For a long time, libpq has had a heuristic rule that it wouldn't
believe large message size words, except for a small number of
message types that are expected to be (potentially) long. This
provides some defense against loss of message-boundary sync and
other corrupted-data cases. The server does something similar,
except that up to now it only limited the lengths of messages
received during the connection authentication phase. Let's
do the same as in libpq and put restrictions on the allowed
length of all messages, while distinguishing between message
types that are expected to be long and those that aren't.
I used a limit of 10000 bytes for non-long messages. (libpq's
corresponding limit is 30000 bytes, but given the asymmetry of
the FE/BE protocol, there's no good reason why the numbers should
be the same.) Experimentation suggests that this is at least a
factor of 10, maybe a factor of 100, more than we really need;
but plenty of daylight seems desirable to avoid false positives.
In any case we can adjust the limit based on beta-test results.
For long messages, set a limit of MaxAllocSize - 1, which is the
most that we can absorb into the StringInfo buffer that the message
is collected in. This just serves to make sure that a bogus message
size is reported as such, rather than as a confusing gripe about
not being able to enlarge a string buffer.
While at it, make sure that non-mainline code paths (such as
COPY FROM STDIN) are as paranoid as SocketBackend is, and validate
the message type code before believing the message length.
This provides an additional guard against getting stuck on corrupted
input.
Discussion: https://postgr.es/m/2003757.1619373089@sss.pgh.pa.us
Commit 8ff1c94649 allowed TRUNCATE command to truncate foreign tables.
Previously the information about "ONLY" options specified in TRUNCATE
command were passed to the foreign data wrapper. Then postgres_fdw
constructed the TRUNCATE command to issue the remote server and
included "ONLY" options in it based on the passed information.
On the other hand, "ONLY" options specified in SELECT, UPDATE or DELETE
have no effect when accessing or modifying the remote table, i.e.,
are not passed to the foreign data wrapper. So it's inconsistent to
make only TRUNCATE command pass the "ONLY" options to the foreign data
wrapper. Therefore this commit changes the TRUNCATE command so that
it doesn't pass the "ONLY" options to the foreign data wrapper,
for the consistency with other statements. Also this commit changes
postgres_fdw so that it always doesn't include "ONLY" options in
the TRUNCATE command that it constructs.
Author: Fujii Masao
Reviewed-by: Bharath Rupireddy, Kyotaro Horiguchi, Justin Pryzby, Zhihong Yu
Discussion: https://postgr.es/m/551ed8c1-f531-818b-664a-2cecdab99cd8@oss.nttdata.com
Previously, we used to use the array of size max_replication_slots to
store stats for replication slots. But that had two problems in the cases
where a message for dropping a slot gets lost: 1) the stats for the new
slot are not recorded if the array is full and 2) writing beyond the end
of the array if the user reduces the max_replication_slots.
This commit uses HTAB for replication slot statistics, resolving both
problems. Now, pgstat_vacuum_stat() search for all the dead replication
slots in stats hashtable and tell the collector to remove them. To avoid
showing the stats for the already-dropped slots, pg_stat_replication_slots
view searches slot stats by the slot name taken from pg_replication_slots.
Also, we send a message for creating a slot at slot creation, initializing
the stats. This reduces the possibility that the stats are accumulated
into the old slot stats when a message for dropping a slot gets lost.
Reported-by: Andres Freund
Author: Sawada Masahiko, test case by Vignesh C
Reviewed-by: Amit Kapila, Vignesh C, Dilip Kumar
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
The Truncate operation acquires an exclusive lock on the target relation
and indexes. It then waits for logical replication of the operation to
finish at commit. Now because we are acquiring the shared lock on the
target index to get index attributes in pgoutput while sending the
changes for the Truncate operation, it leads to a deadlock.
Actually, we don't need to acquire a lock on the target index as we build
the cache entry using a historic snapshot and all the later changes are
absorbed while decoding WAL. So, we wrote a special purpose function for
logical replication to get a bitmap of replica identity attribute numbers
where we get that information without locking the target index.
We decided not to backpatch this as there doesn't seem to be any field
complaint about this issue since it was introduced in commit 5dfd1e5a in
v11.
Reported-by: Haiying Tang
Author: Takamichi Osumi, test case by Li Japin
Reviewed-by: Amit Kapila, Ajin Cherian
Discussion: https://postgr.es/m/OS0PR01MB6113C2499C7DC70EE55ADB82FB759@OS0PR01MB6113.jpnprd01.prod.outlook.com
We send the prepare for the concurrently aborted xacts so that later when
rollback prepared is decoded and sent, the downstream should be able to
rollback such a xact. For 'streaming' case (when we send changes for
in-progress transactions), we were sending prepare twice when concurrent
abort was detected.
Author: Peter Smith
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/f82133c6-6055-b400-7922-97dae9f2b50b@enterprisedb.com
Creating a trigger on a relation to which an apply operation is
triggered would cause a relation leak once the change gets committed,
as the executor would miss that the relation needs to be closed
beforehand. This issue got introduced with the refactoring done in
1375422c, where it becomes necessary to track relations within
es_opened_result_relations to make sure that they are closed.
We have discussed using ExecInitResultRelation() coupled with
ExecCloseResultRelations() for the relations in need of tracking by the
apply operations in the subscribers, which would simplify greatly the
opening and closing of indexes, but this requires a larger rework and
reorganization of the worker code, particularly for the tuple routing
part. And that's not really welcome post feature freeze. So, for now,
settle down to the same solution as TRUNCATE which is to fill in
es_opened_result_relations with the relation opened, to make sure that
ExecGetTriggerResultRel() finds them and that they get closed.
The code is lightly refactored so as a relation is not registered three
times for each DML code path, making the whole a bit easier to follow.
Reported-by: Tang Haiying, Shi Yu, Hou Zhijie
Author: Amit Langote, Masahiko Sawada, Hou Zhijie
Reviewed-by: Amit Kapila, Michael Paquier
Discussion: https://postgr.es/m/OS0PR01MB611383FA0FE92EB9DE21946AFB769@OS0PR01MB6113.jpnprd01.prod.outlook.com
This adds the statistics about total transactions count and total
transaction data logically sent to the decoding output plugin from
ReorderBuffer. Users can query the pg_stat_replication_slots view to check
these stats.
Suggested-by: Andres Freund
Author: Vignesh C and Amit Kapila
Reviewed-by: Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
This will make it consistent with the other usage of slotname in the code.
In the passing, change pgstat_report_replslot signature to use a structure
rather than multiple parameters.
Reported-by: Andres Freund
Author: Vignesh C
Reviewed-by: Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
This commit introduces new foreign data wrapper API for TRUNCATE.
It extends TRUNCATE command so that it accepts foreign tables as
the targets to truncate and invokes that API. Also it extends postgres_fdw
so that it can issue TRUNCATE command to foreign servers, by adding
new routine for that TRUNCATE API.
The information about options specified in TRUNCATE command, e.g.,
ONLY, CACADE, etc is passed to FDW via API. The list of foreign tables to
truncate is also passed to FDW. FDW truncates the foreign data sources
that the passed foreign tables specify, based on those information.
For example, postgres_fdw constructs TRUNCATE command using them
and issues it to the foreign server.
For performance, TRUNCATE command invokes the FDW routine for
TRUNCATE once per foreign server that foreign tables to truncate belong to.
Author: Kazutaka Onishi, Kohei KaiGai, slightly modified by Fujii Masao
Reviewed-by: Bharath Rupireddy, Michael Paquier, Zhihong Yu, Alvaro Herrera, Stephen Frost, Ashutosh Bapat, Amit Langote, Daniel Gustafsson, Ibrar Ahmed, Fujii Masao
Discussion: https://postgr.es/m/CAOP8fzb_gkReLput7OvOK+8NHgw-RKqNv59vem7=524krQTcWA@mail.gmail.com
Discussion: https://postgr.es/m/CAJuF6cMWDDqU-vn_knZgma+2GMaout68YUgn1uyDnexRhqqM5Q@mail.gmail.com
Teach xlogreader.c to decode its output into a circular buffer, to
support optimizations based on looking ahead.
* XLogReadRecord() works as before, consuming records one by one, and
allowing them to be examined via the traditional XLogRecGetXXX()
macros.
* An alternative new interface XLogNextRecord() is added that returns
pointers to DecodedXLogRecord structs that can be examined directly.
* XLogReadAhead() provides a second cursor that lets you see
further ahead, as long as data is available and there is enough space
in the decoding buffer. This returns DecodedXLogRecord pointers to the
caller, but also adds them to a queue of records that will later be
consumed by XLogNextRecord()/XLogReadRecord().
The buffer's size is controlled with wal_decode_buffer_size. The buffer
could potentially be placed into shared memory, for future projects.
Large records that don't fit in the circular buffer are called
"oversized" and allocated separately with palloc().
Discussion: https://postgr.es/m/CA+hUKGJ4VJN8ttxScUFM8dOKX0BrBiboo5uz1cq=AovOddfHpA@mail.gmail.com
Previously, the XLogReader module would fetch new input data using a
callback function. Redesign the interface so that it tells the caller
to insert more data with a special return value instead. This API suits
later patches for prefetching, encryption and maybe other future
projects that would otherwise require continually extending the callback
interface.
As incidental cleanup work, move global variables readOff, readLen and
readSegNo inside XlogReaderState.
Author: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Author: Heikki Linnakangas <hlinnaka@iki.fi> (parts of earlier version)
Reviewed-by: Antonin Houska <ah@cybertec.at>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Takashi Menjo <takashi.menjo@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20190418.210257.43726183.horiguchi.kyotaro%40lab.ntt.co.jp
Arrange to do some things on-demand, rather than immediately during
executor startup, because there's a fair chance of never having to do
them at all:
* Don't open result relations' indexes until needed.
* Don't initialize partition tuple routing, nor the child-to-root
tuple conversion map, until needed.
This wins in UPDATEs on partitioned tables when only some of the
partitions will actually receive updates; with larger partition
counts the savings is quite noticeable. Also, we can remove some
sketchy heuristics in ExecInitModifyTable about whether to set up
tuple routing.
Also, remove execPartition.c's private hash table tracking which
partitions were already opened by the ModifyTable node. Instead
use the hash added to ModifyTable itself by commit 86dc90056.
To allow lazy computation of the conversion maps, we now set
ri_RootResultRelInfo in all child ResultRelInfos. We formerly set it
only in some, not terribly well-defined, cases. This has user-visible
side effects in that now more error messages refer to the root
relation instead of some partition (and provide error data in the
root's column order, too). It looks to me like this is a strict
improvement in consistency, so I don't have a problem with the
output changes visible in this commit.
Extracted from a larger patch, which seemed to me to be too messy
to push in one commit.
Amit Langote, reviewed at different times by Heikki Linnakangas and
myself
Discussion: https://postgr.es/m/CA+HiwqG7ZruBmmih3wPsBZ4s0H2EhywrnXEduckY5Hr3fWzPWA@mail.gmail.com
Retry the call to heap_prune_page() in rare cases where there is
disagreement between the heap_prune_page() call and the call to
HeapTupleSatisfiesVacuum() that immediately follows. Disagreement is
possible when a concurrently-aborted transaction makes a tuple DEAD
during the tiny window between each step. This was the only case where
a tuple considered DEAD by VACUUM still had storage following pruning.
VACUUM's definition of dead tuples is now uniformly simple and
unambiguous: dead tuples from each page are always LP_DEAD line pointers
that were encountered just after we performed pruning (and just before
we considered freezing remaining items with tuple storage).
Eliminating the tupgone=true special case enables INDEX_CLEANUP=off
style skipping of index vacuuming that takes place based on flexible,
dynamic criteria. The INDEX_CLEANUP=off case had to know about skipping
indexes up-front before now, due to a subtle interaction with the
special case (see commit dd695979) -- this was a special case unto
itself. Now there are no special cases. And so now it won't matter
when or how we decide to skip index vacuuming: it won't affect how
pruning behaves, and it won't be affected by any of the implementation
details of pruning or freezing.
Also remove XLOG_HEAP2_CLEANUP_INFO records. These are no longer
necessary because we now rely entirely on heap pruning taking care of
recovery conflicts. There is no longer any need to generate recovery
conflicts for DEAD tuples that pruning just missed. This also means
that heap vacuuming now uses exactly the same strategy for recovery
conflicts as index vacuuming always has: REDO routines never need to
process a latestRemovedXid from the WAL record, since earlier REDO of
the WAL record from pruning is sufficient in all cases. The generic
XLOG_HEAP2_CLEAN record type is now split into two new record types to
reflect this new division (these are called XLOG_HEAP2_PRUNE and
XLOG_HEAP2_VACUUM).
Also stop acquiring a super-exclusive lock for heap pages when they're
vacuumed during VACUUM's second heap pass. A regular exclusive lock is
enough. This is correct because heap page vacuuming is now strictly a
matter of setting the LP_DEAD line pointers to LP_UNUSED. No other
backend can have a pointer to a tuple located in a pinned buffer that
can be invalidated by a concurrent heap page vacuum operation.
Heap vacuuming can now be thought of as conceptually similar to index
vacuuming and conceptually dissimilar to heap pruning. Heap pruning now
has sole responsibility for anything involving the logical contents of
the database (e.g., managing transaction status information, recovery
conflicts, considering what to do with HOT chains). Index vacuuming and
heap vacuuming are now only concerned with recycling garbage items from
physical data structures that back the logical database.
Bump XLOG_PAGE_MAGIC due to pruning and heap page vacuum WAL record
changes.
Credit for the idea of retrying pruning a page to avoid the tupgone case
goes to Andres Freund.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andres Freund <andres@anarazel.de>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznneCXTzuFmcwx_EyRQgfsfJAAsu+CsqRFmFXCAar=nJw@mail.gmail.com
The output plugin accepts a new parameter (messages) that controls if
logical decoding messages are written into the replication stream. It is
useful for those clients that use pgoutput as an output plugin and needs
to process messages that were written by pg_logical_emit_message().
Although logical streaming replication protocol supports logical
decoding messages now, logical replication does not use this feature yet.
Author: David Pirotte, Euler Taveira
Reviewed-by: Euler Taveira, Andres Freund, Ashutosh Bapat, Amit Kapila
Discussion: https://postgr.es/m/CADK3HHJ-+9SO7KuRLH=9Wa1rAo60Yreq1GFNkH_kd0=CdaWM+A@mail.gmail.com
Instead of using multiple parameters in parse_ouput_parameters function
signature, use the struct PGOutputData that encapsulates all pgoutput
options. It will be useful for future work where we need to add other
options in pgoutput.
Author: Euler Taveira
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CADK3HHJ-+9SO7KuRLH=9Wa1rAo60Yreq1GFNkH_kd0=CdaWM+A@mail.gmail.com
It is possible that while decoding a prepared transaction, it gets aborted
concurrently via a ROLLBACK PREPARED command. In that case, we were
skipping all the changes and directly sending Rollback Prepared when we
find the same in WAL. However, the downstream has no idea of the GID of
such a transaction. So, ensure to send prepare even when a concurrent
abort is detected.
Author: Ajin Cherian
Reviewed-by: Markus Wanner, Amit Kapila
Discussion: https://postgr.es/m/f82133c6-6055-b400-7922-97dae9f2b50b@enterprisedb.com
Put the remote end's error message into the primary error string,
instead of relegating it to errdetail(). Although this could end up
being awkward if the remote sends us a really long error message,
it seems more in keeping with our message style guidelines, and more
helpful in situations where the errdetail could get dropped.
Peter Smith
Discussion: https://postgr.es/m/CAHut+Ps-Qv2yQceCwobQDP0aJOkfDzRFrOaR6+2Op2K=WHGeWg@mail.gmail.com
Along with gid, this provides a different way to identify the transaction.
The users that use xid in some way to prepare the transactions can use it
to filter prepare transactions. The later commands COMMIT PREPARED or
ROLLBACK PREPARED carries both identifiers, providing an output plugin the
choice of what to use.
Author: Markus Wanner
Reviewed-by: Vignesh C, Amit Kapila
Discussion: https://postgr.es/m/ee280000-7355-c4dc-e47b-2436e7be959c@enterprisedb.com
Commit de829ddf23 added wait event WalrcvExit. But its name is not
consistent with other wait events like WalReceiverMain or
WalReceiverWaitStart, etc. So this commit renames WalrcvExit to
WalReceiverExit.
Author: Fujii Masao
Reviewed-by: Thomas Munro
Discussion: https://postgr.es/m/cced9995-8fa2-7b22-9d91-3f22a2b8c23c@oss.nttdata.com
There is now a per-column COMPRESSION option which can be set to pglz
(the default, and the only option in up until now) or lz4. Or, if you
like, you can set the new default_toast_compression GUC to lz4, and
then that will be the default for new table columns for which no value
is specified. We don't have lz4 support in the PostgreSQL code, so
to use lz4 compression, PostgreSQL must be built --with-lz4.
In general, TOAST compression means compression of individual column
values, not the whole tuple, and those values can either be compressed
inline within the tuple or compressed and then stored externally in
the TOAST table, so those properties also apply to this feature.
Prior to this commit, a TOAST pointer has two unused bits as part of
the va_extsize field, and a compessed datum has two unused bits as
part of the va_rawsize field. These bits are unused because the length
of a varlena is limited to 1GB; we now use them to indicate the
compression type that was used. This means we only have bit space for
2 more built-in compresison types, but we could work around that
problem, if necessary, by introducing a new vartag_external value for
any further types we end up wanting to add. Hopefully, it won't be
too important to offer a wide selection of algorithms here, since
each one we add not only takes more coding but also adds a build
dependency for every packager. Nevertheless, it seems worth doing
at least this much, because LZ4 gets better compression than PGLZ
with less CPU usage.
It's possible for LZ4-compressed datums to leak into composite type
values stored on disk, just as it is for PGLZ. It's also possible for
LZ4-compressed attributes to be copied into a different table via SQL
commands such as CREATE TABLE AS or INSERT .. SELECT. It would be
expensive to force such values to be decompressed, so PostgreSQL has
never done so. For the same reasons, we also don't force recompression
of already-compressed values even if the target table prefers a
different compression method than was used for the source data. These
architectural decisions are perhaps arguable but revisiting them is
well beyond the scope of what seemed possible to do as part of this
project. However, it's relatively cheap to recompress as part of
VACUUM FULL or CLUSTER, so this commit adjusts those commands to do
so, if the configured compression method of the table happens not to
match what was used for some column value stored therein.
Dilip Kumar. The original patches on which this work was based were
written by Ildus Kurbangaliev, and those were patches were based on
even earlier work by Nikita Glukhov, but the design has since changed
very substantially, since allow a potentially large number of
compression methods that could be added and dropped on a running
system proved too problematic given some of the architectural issues
mentioned above; the choice of which specific compression method to
add first is now different; and a lot of the code has been heavily
refactored. More recently, Justin Przyby helped quite a bit with
testing and reviewing and this version also includes some code
contributions from him. Other design input and review from Tomas
Vondra, Álvaro Herrera, Andres Freund, Oleg Bartunov, Alexander
Korotkov, and me.
Discussion: http://postgr.es/m/20170907194236.4cefce96%40wp.localdomain
Discussion: http://postgr.es/m/CAFiTN-uUpX3ck%3DK0mLEk-G_kUQY%3DSNOTeqdaNRR9FMdQrHKebw%40mail.gmail.com
We leaked the error report from PQconninfoParse, when there was
one. It seems unlikely that real usage patterns would repeat
the failure often enough to create serious bloat, but let's
back-patch anyway to keep the code similar in all branches.
Found via valgrind testing.
Back-patch to v10 where this code was added.
Discussion: https://postgr.es/m/3816764.1616104288@sss.pgh.pa.us
While looking at Robert Foggia's report, I noticed a passel of
other issues in the same area:
* The scheme for backslash-quoting newlines in pathnames is just
wrong; it will misbehave if the last ordinary character in a pathname
is a backslash. I'm not sure why we're bothering to allow newlines
in tablespace paths, but if we're going to do it we should do it
without introducing other problems. Hence, backslashes themselves
have to be backslashed too.
* The author hadn't read the sscanf man page very carefully, because
this code would drop any leading whitespace from the path. (I doubt
that a tablespace path with leading whitespace could happen in
practice; but if we're bothering to allow newlines in the path, it
sure seems like leading whitespace is little less implausible.) Using
sscanf for the task of finding the first space is overkill anyway.
* While I'm not 100% sure what the rationale for escaping both \r and
\n is, if the idea is to allow Windows newlines in the file then this
code failed, because it'd throw an error if it saw \r followed by \n.
* There's no cross-check for an incomplete final line in the map file,
which would be a likely apparent symptom of the improper-escaping
bug.
On the generation end, aside from the escaping issue we have:
* If needtblspcmapfile is true then do_pg_start_backup will pass back
escaped strings in tablespaceinfo->path values, which no caller wants
or is prepared to deal with. I'm not sure if there's a live bug from
that, but it looks like there might be (given the dubious assumption
that anyone actually has newlines in their tablespace paths).
* It's not being very paranoid about the possibility of random stuff
in the pg_tblspc directory. IMO we should ignore anything without an
OID-like name.
The escaping rule change doesn't seem back-patchable: it'll require
doubling of backslashes in the tablespace_map file, which is basically
a basebackup format change. The odds of that causing trouble are
considerably more than the odds of the existing bug causing trouble.
The rest of this seems somewhat unlikely to cause problems too,
so no back-patch.
Commit ce0fdbfe97 made tablesync slots permanent and allow Drop
Subscription to drop such slots. However, it is possible that before
tablesync worker could get the acknowledgment of slot creation, drop
subscription stops it and that can lead to a dangling slot on the
publisher. Prevent cancel/die interrupts while creating a slot in the
tablesync worker.
Reported-by: Thomas Munro as per buildfarm
Author: Amit Kapila
Reviewed-by: Vignesh C, Takamichi Osumi
Discussion: https://postgr.es/m/CA+hUKGJG9dWpw1cOQ2nzWU8PHjm=PTraB+KgE5648K9nTfwvxg@mail.gmail.com
Pipeline mode in libpq lets an application avoid the Sync messages in
the FE/BE protocol that are implicit in the old libpq API after each
query. The application can then insert Sync at its leisure with a new
libpq function PQpipelineSync. This can lead to substantial reductions
in query latency.
Co-authored-by: Craig Ringer <craig.ringer@enterprisedb.com>
Co-authored-by: Matthieu Garrigues <matthieu.garrigues@gmail.com>
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Aya Iwata <iwata.aya@jp.fujitsu.com>
Reviewed-by: Daniel Vérité <daniel@manitou-mail.org>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Kirk Jamison <k.jamison@fujitsu.com>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: Nikhil Sontakke <nikhils@2ndquadrant.com>
Reviewed-by: Vaishnavi Prabakaran <VaishnaviP@fast.au.fujitsu.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CAMsr+YFUjJytRyV4J-16bEoiZyH=4nj+sQ7JP9ajwz=B4dMMZw@mail.gmail.com
Discussion: https://postgr.es/m/CAJkzx4T5E-2cQe3dtv2R78dYFvz+in8PY7A8MArvLhs_pg75gg@mail.gmail.com
Commit 0aa8a01d04 extends the output plugin API to allow decoding of
prepared xacts and allowed the user to enable/disable the two-phase option
via pg_logical_slot_get_changes(). This can lead to a problem such that
the first time when it gets changes via pg_logical_slot_get_changes()
without two_phase option enabled it will not get the prepared even though
prepare is after consistent snapshot. Now next time during getting changes,
if the two_phase option is enabled it can skip prepare because by that
time start decoding point has been moved. So the user will only get commit
prepared.
Allow to enable/disable this option at the create slot time and default
will be false. It will break the existing slots which is fine in a major
release.
Author: Ajin Cherian
Reviewed-by: Amit Kapila and Vignesh C
Discussion: https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com
In commit a271a1b50e, we allowed decoding at prepare time and the prepare
was decoded again if there is a restart after decoding it. It was done
that way because we can't distinguish between the cases where we have not
decoded the prepare because it was prior to consistent snapshot or we have
decoded it earlier but restarted. To distinguish between these two cases,
we have introduced an initial_consistent_point at the slot level which is
an LSN at which we found a consistent point at the time of slot creation.
This is also the point where we have exported a snapshot for the initial
copy. So, prepare transaction prior to this point are sent along with
commit prepared.
This commit bumps SNAPBUILD_VERSION because of change in SnapBuild. It
will break existing slots which is fine in a major release.
Author: Ajin Cherian, based on idea by Andres Freund
Reviewed-by: Amit Kapila and Vignesh C
Discussion: https://postgr.es/m/d0f60d60-133d-bf8d-bd70-47784d8fabf3@enterprisedb.com
This avoids the need to set up and tear down a fresh WaitEventSet every
time we need need to wait. We have to add an explicit exit on
postmaster exit (FeBeWaitSet isn't set up to do that automatically), so
move the code to do that into a new function to avoid repetition.
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com
Commit a271a1b50e introduced decoding at prepare time in ReorderBuffer.
This can lead to deadlock for out-of-core logical replication solutions
that uses this feature to build distributed 2PC in case such transactions
lock [user] catalog tables exclusively. They need to inform users to not
have locks on catalog tables (via explicit LOCK command) in such
transactions.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/20210222222847.tpnb6eg3yiykzpky@alap3.anarazel.de
We don't have anything to decode in a transaction if ReorderBufferTXN
doesn't exist by the time we decode the commit prepared. So don't create a
new ReorderBufferTXN here. This is an oversight in commit a271a1b5.
Reported-by: Markus Wanner
Discussion: https://postgr.es/m/dbec82e2-dbd7-95a2-c6b6-e488cbbdf853@bluegap.ch
Commit 2c8dd05d6c added the atomic variable writtenUpto into
walreceiver's shared memory information. It's initialized only
when walreceiver started up but could be read via pg_stat_wal_receiver
view anytime, i.e., even before it's initialized. In the server built
with --disable-atomics and --disable-spinlocks, this uninitialized
atomic variable read could cause "invalid spinlock number: 0" error.
This commit changed writtenUpto so that it's initialized at
the postmaster startup, to avoid the uninitialized variable read
via pg_stat_wal_receiver and fix the error.
Also this commit moved the read of writtenUpto after the release
of spinlock protecting walreceiver's shared variables. This is
necessary to prevent new spinlock from being taken by atomic
variable read while holding another spinlock, and to shorten
the spinlock duration. This change leads writtenUpto not to be
consistent with the other walreceiver's shared variables protected
by a spinlock. But this is OK because writtenUpto should not be
used for data integrity checks.
Back-patch to v13 where commit 2c8dd05d6c introduced the bug.
Author: Fujii Masao
Reviewed-by: Michael Paquier, Thomas Munro, Andres Freund
Discussion: https://postgr.es/m/7ef8708c-5b6b-edd3-2cf2-7783f1c7c175@oss.nttdata.com
This issue exists from the inception of this code (PG-10) but got exposed
by the recent commit ce0fdbfe97 where we are using origins in tablesync
workers. The problem was that we were sometimes sending the prepare_write
('w') message but then the actual message was not being sent and on the
subscriber side, we always expect a message after prepare_write message
which led to this bug.
I refrained from backpatching this because there is no way in the core
code to hit this prior to commit ce0fdbfe97 and we haven't received any
complaints so far.
Reported-by: Erik Rijkers
Author: Amit Kapila and Vignesh C
Tested-by: Erik Rijkers
Discussion: https://postgr.es/m/1295168140.139428.1613133237154@webmailclassic.xs4all.nl
In 955a684e04 we fixed a bug in initial snapshot creation. In the
course of which several members of struct SnapBuild were obsoleted. As
SnapBuild is serialized to disk we couldn't change the memory layout.
Unfortunately I subsequently forgot about removing the backward compat
gunk, but luckily Heikki just reminded me.
This commit bumps SNAPBUILD_VERSION, therefore breaking existing
slots (which is fine in a major release).
Author: Andres Freund
Reminded-By: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/c94be044-818f-15e3-1ad3-7a7ae2dfed0a@iki.fi
With its current design, a careless use of pg_cryptohash_final() could
would result in an out-of-bound write in memory as the size of the
destination buffer to store the result digest is not known to the
cryptohash internals, without the caller knowing about that. This
commit adds a new argument to pg_cryptohash_final() to allow such sanity
checks, and implements such defenses.
The internals of SCRAM for HMAC could be tightened a bit more, but as
everything is based on SCRAM_KEY_LEN with uses particular to this code
there is no need to complicate its interface more than necessary, and
this comes back to the refactoring of HMAC in core. Except that, this
minimizes the uses of the existing DIGEST_LENGTH variables, relying
instead on sizeof() for the result sizes. In ossp-uuid, this also makes
the code more defensive, as it already relied on dce_uuid_t being at
least the size of a MD5 digest.
This is in philosophy similar to cfc40d3 for base64.c and aef8948 for
hex.c.
Reported-by: Ranier Vilela
Author: Michael Paquier, Ranier Vilela
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CAEudQAoqEGmcff3J4sTSV-R_16Monuz-UpJFbf_dnVH=APr02Q@mail.gmail.com
For the initial table data synchronization in logical replication, we use
a single transaction to copy the entire table and then synchronize the
position in the stream with the main apply worker.
There are multiple downsides of this approach: (a) We have to perform the
entire copy operation again if there is any error (network breakdown,
error in the database operation, etc.) while we synchronize the WAL
position between tablesync worker and apply worker; this will be onerous
especially for large copies, (b) Using a single transaction in the
synchronization-phase (where we can receive WAL from multiple
transactions) will have the risk of exceeding the CID limit, (c) The slot
will hold the WAL till the entire sync is complete because we never commit
till the end.
This patch solves all the above downsides by allowing multiple
transactions during the tablesync phase. The initial copy is done in a
single transaction and after that, we commit each transaction as we
receive. To allow recovery after any error or crash, we use a permanent
slot and origin to track the progress. The slot and origin will be removed
once we finish the synchronization of the table. We also remove slot and
origin of tablesync workers if the user performs DROP SUBSCRIPTION .. or
ALTER SUBSCRIPTION .. REFERESH and some of the table syncs are still not
finished.
The commands ALTER SUBSCRIPTION ... REFRESH PUBLICATION and
ALTER SUBSCRIPTION ... SET PUBLICATION ... with refresh option as true
cannot be executed inside a transaction block because they can now drop
the slots for which we have no provision to rollback.
This will also open up the path for logical replication of 2PC
transactions on the subscriber side. Previously, we can't do that because
of the requirement of maintaining a single transaction in tablesync
workers.
Bump catalog version due to change of state in the catalog
(pg_subscription_rel).
Author: Peter Smith, Amit Kapila, and Takamichi Osumi
Reviewed-by: Ajin Cherian, Petr Jelinek, Hou Zhijie and Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1KHJxaZS-fod-0fey=0tq3=Gkn4ho=8N4-5HWiCfu0H1A@mail.gmail.com
Currently, we get the origin id from the name and then drop the origin by
taking ExclusiveLock on ReplicationOriginRelationId. So, two concurrent
sessions can get the id from the name at the same time and then when they
try to drop the origin, one of the sessions will get the either
"tuple concurrently deleted" or "cache lookup failed for replication
origin ..".
To prevent this race condition we do the entire operation under lock. This
obviates the need for replorigin_drop() API and we have removed it so if
any extension authors are using it they need to instead use
replorigin_drop_by_name. See it's usage in pg_replication_origin_drop().
Author: Peter Smith
Reviewed-by: Amit Kapila, Euler Taveira, Petr Jelinek, and Alvaro
Herrera
Discussion: https://www.postgresql.org/message-id/CAHut%2BPuW8DWV5fskkMWWMqzt-x7RPcNQOtJQBp6SdwyRghCk7A%40mail.gmail.com
Up until now, we've held this lock when performing a checkpoint or
restartpoint, but commit 076a055acf back
in 2004 and commit 7e48b77b1c from 2009,
taken together, have removed all need for this. In the present code,
there's only ever one process entitled to attempt a checkpoint: either
the checkpointer, during normal operation, or the postmaster, during
single-user operation. So, we don't need the lock.
One possible concern in making this change is that it means that
a substantial amount of code where HOLD_INTERRUPTS() was previously
in effect due to the preceding LWLockAcquire() will now be
running without that. This could mean that ProcessInterrupts()
gets called in places from which it didn't before. However, this
seems unlikely to do very much, because the checkpointer doesn't
have any signal mapped to die(), so it's not clear how,
for example, ProcDiePending = true could happen in the first
place. Similarly with ClientConnectionLost and recovery conflicts.
Also, if there are any such problems, we might want to fix them
rather than reverting this, since running lots of code with
interrupt handling suspended is generally bad.
Patch by me, per an inquiry by Amul Sul. Review by Tom Lane
and Michael Paquier.
Discussion: http://postgr.es/m/CAAJ_b97XnBBfYeSREDJorFsyoD1sHgqnNuCi=02mNQBUMnA=FA@mail.gmail.com
Commit 69bd60672 fixed the initialization of streamed transactions for
RelationSyncEntry. It forgot to initialize the publication actions while
invalidating the RelationSyncEntry due to which even though the relation
is dropped from a particular publication we still publish its changes. Fix
it by initializing pubactions when entry got invalidated.
Author: Japin Li and Bharath Rupireddy
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CALj2ACV+0UFpcZs5czYgBpujM9p0Hg1qdOZai_43OU7bqHU_xw@mail.gmail.com
Commit 709d003fbd refactored WAL-reading code, but accidentally caused
WalSndSegmentOpen() to fail to follow a timeline switch while reading from
a historic timeline. This issue caused a standby to fail to follow a primary
on a newer timeline when WAL archiving is enabled.
If there is a timeline switch within the segment, WalSndSegmentOpen() should
read from the WAL segment belonging to the new timeline. But previously
since it failed to follow a timeline switch, it tried to read the WAL segment
with old timeline. When WAL archiving is enabled, that WAL segment with
old timeline doesn't exist because it's renamed to .partial. This leads
a primary to have tried to read non-existent WAL segment, and which caused
replication to faill with the error "ERROR: requested WAL segment ... has
already been removed".
This commit fixes WalSndSegmentOpen() so that it's able to follow a timeline
switch, to ensure that a standby is able to follow a primary on a newer
timeline even when WAL archiving is enabled.
This commit also adds the regression test to check whether a standby is
able to follow a primary on a newer timeline when WAL archiving is enabled.
Back-patch to v13 where the bug was introduced.
Reported-by: Kyotaro Horiguchi
Author: Kyotaro Horiguchi, tweaked by Fujii Masao
Reviewed-by: Alvaro Herrera, Fujii Masao
Discussion: https://postgr.es/m/20201209.174314.282492377848029776.horikyota.ntt@gmail.com
This commit addresses some issues with c3826f83 that moved the hex
decoding routine to src/common/:
- The decoding function lacked overflow checks, so when used for
security-related features it was an open door to out-of-bound writes if
not carefully used that could remain undetected. Like the base64
routines already in src/common/ used by SCRAM, this routine is reworked
to check for overflows by having the size of the destination buffer
passed as argument, with overflows checked before doing any writes.
- The encoding routine was missing. This is moved to src/common/ and
it gains the same overflow checks as the decoding part.
On failure, the hex routines of src/common/ issue an error as per the
discussion done to make them usable by frontend tools, but not by shared
libraries. Note that this is why ECPG is left out of this commit, and
it still includes a duplicated logic doing hex encoding and decoding.
While on it, this commit uses better variable names for the source and
destination buffers in the existing escape and base64 routines in
encode.c and it makes them more robust to overflow detection. The
previous core code issued a FATAL after doing out-of-bound writes if
going through the SQL functions, which would be enough to detect
problems when working on changes that impacted this area of the
code. Instead, an error is issued before doing an out-of-bound write.
The hex routines were being directly called for bytea conversions and
backup manifests without such sanity checks. The current calls happen
to not have any problems, but careless uses of such APIs could easily
lead to CVE-class bugs.
Author: Bruce Momjian, Michael Paquier
Reviewed-by: Sehrope Sarkuni
Discussion: https://postgr.es/m/20201231003557.GB22199@momjian.us
Add an executor aminsert() hint mechanism that informs index AMs that
the incoming index tuple (the tuple that accompanies the hint) is not
being inserted by execution of an SQL statement that logically modifies
any of the index's key columns.
The hint is received by indexes when an UPDATE takes place that does not
apply an optimization like heapam's HOT (though only for indexes where
all key columns are logically unchanged). Any index tuple that receives
the hint on insert is expected to be a duplicate of at least one
existing older version that is needed for the same logical row. Related
versions will typically be stored on the same index page, at least
within index AMs that apply the hint.
Recognizing the difference between MVCC version churn duplicates and
true logical row duplicates at the index AM level can help with cleanup
of garbage index tuples. Cleanup can intelligently target tuples that
are likely to be garbage, without wasting too many cycles on less
promising tuples/pages (index pages with little or no version churn).
This is infrastructure for an upcoming commit that will teach nbtree to
perform bottom-up index deletion. No index AM actually applies the hint
just yet.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Victor Yegorov <vyegorov@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=CEKFa74EScx_hFVshCOn6AA5T-ajFASTdzipdkLTNQQ@mail.gmail.com
This patch allows PREPARE-time decoding of two-phase transactions (if the
output plugin supports this capability), in which case the transactions
are replayed at PREPARE and then committed later when COMMIT PREPARED
arrives.
Now that we decode the changes before the commit, the concurrent aborts
may cause failures when the output plugin consults catalogs (both system
and user-defined).
We detect such failures with a special sqlerrcode
ERRCODE_TRANSACTION_ROLLBACK introduced by commit 7259736a6e and stop
decoding the remaining changes. Then we rollback the changes when rollback
prepared is encountered.
Author: Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Peter Smith, Sawada Masahiko, Arseny Sher, and Dilip Kumar
Tested-by: Takamichi Osumi
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/CAMGcDxeqEpWj3fTXwqhSwBdXd2RS9jzwWscO-XbeCfso6ts3+Q@mail.gmail.com
This adds six methods to the output plugin API, adding support for
streaming changes of two-phase transactions at prepare time.
* begin_prepare
* filter_prepare
* prepare
* commit_prepared
* rollback_prepared
* stream_prepare
Most of this is a simple extension of the existing methods, with the
semantic difference that the transaction is not yet committed and maybe
aborted later.
Until now two-phase transactions were translated into regular transactions
on the subscriber, and the GID was not forwarded to it. None of the
two-phase commands were communicated to the subscriber.
This patch provides the infrastructure for logical decoding plugins to be
informed of two-phase commands Like PREPARE TRANSACTION, COMMIT PREPARED
and ROLLBACK PREPARED commands with the corresponding GID.
This also extends the 'test_decoding' plugin, implementing these new
methods.
This commit simply adds these new APIs and the upcoming patch to "allow
the decoding at prepare time in ReorderBuffer" will use these APIs.
Author: Ajin Cherian and Amit Kapila based on previous work by Nikhil Sontakke and Stas Kelvich
Reviewed-by: Amit Kapila, Peter Smith, Sawada Masahiko, and Dilip Kumar
Discussion:
https://postgr.es/m/02DA5F5E-CECE-4D9C-8B4B-418077E2C010@postgrespro.ruhttps://postgr.es/m/CAMGcDxeqEpWj3fTXwqhSwBdXd2RS9jzwWscO-XbeCfso6ts3+Q@mail.gmail.com
The patch needs test cases, reorganization, and cfbot testing.
Technically reverts commits 5c31afc49d..e35b2bad1a (exclusive/inclusive)
and 08db7c63f3..ccbe34139b.
Reported-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/E1ktAAG-0002V2-VB@gemulon.postgresql.org
This adds a key management system that stores (currently) two data
encryption keys of length 128, 192, or 256 bits. The data keys are
AES256 encrypted using a key encryption key, and validated via GCM
cipher mode. A command to obtain the key encryption key must be
specified at initdb time, and will be run at every database server
start. New parameters allow a file descriptor open to the terminal to
be passed. pg_upgrade support has also been added.
Discussion: https://postgr.es/m/CA+fd4k7q5o6Nc_AaX6BcYM9yqTbC6_pnH-6nSD=54Zp6NBQTCQ@mail.gmail.com
Discussion: https://postgr.es/m/20201202213814.GG20285@momjian.us
Author: Masahiko Sawada, me, Stephen Frost
The comments atop of this function describes behaviour in case of a
transactional WAL message only, but it accepts both transactional and
non-transactional WAL messages. Update the comments to describe
behaviour in case of non-transactional WAL message as well.
Ashutosh Bapat, rephrased by Amit Kapila
Discussion: https://postgr.es/m/CAGEoWWTTzNzHOi8bj0wfAo1siGi-YEh6wqH1oaz4DrkTJ6HbTQ@mail.gmail.com
Invent a new flag bit HASH_STRINGS to specify C-string hashing, which
was formerly the default; and add assertions insisting that exactly
one of the bits HASH_STRINGS, HASH_BLOBS, and HASH_FUNCTION be set.
This is in hopes of preventing recurrences of the type of oversight
fixed in commit a1b8aa1e4 (i.e., mistakenly omitting HASH_BLOBS).
Also, when HASH_STRINGS is specified, insist that the keysize be
more than 8 bytes. This is a heuristic, but it should catch
accidental use of HASH_STRINGS for integer or pointer keys.
(Nearly all existing use-cases set the keysize to NAMEDATALEN or
more, so there's little reason to think this restriction should
be problematic.)
Tweak hash_create() to insist that the HASH_ELEM flag be set, and
remove the defaults it had for keysize and entrysize. Since those
defaults were undocumented and basically useless, no callers
omitted HASH_ELEM anyway.
Also, remove memset's zeroing the HASHCTL parameter struct from
those callers that had one. This has never been really necessary,
and while it wasn't a bad coding convention it was confusing that
some callers did it and some did not. We might as well save a few
cycles by standardizing on "not".
Also improve the documentation for hash_create().
In passing, improve reinit.c's usage of a hash table by storing
the key as a binary Oid rather than a string; and, since that's
a temporary hash table, allocate it in CurrentMemoryContext for
neatness.
Discussion: https://postgr.es/m/590625.1607878171@sss.pgh.pa.us
User-visible log messages should go through ereport(), so they are
subject to translation. Many remaining elog(LOG) calls are really
debugging calls.
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://www.postgresql.org/message-id/flat/92d6f545-5102-65d8-3c87-489f71ea0a37%40enterprisedb.com
We start recording changes in ReorderBufferTXN even before we reach
SNAPBUILD_CONSISTENT state so that if the commit is encountered after
reaching that we should be able to send the changes of the entire transaction.
Now, while recording changes if the reorder buffer memory has exceeded
logical_decoding_work_mem then we can start streaming if it is allowed and
we haven't yet streamed that data. However, we must not allow streaming to
start unless the snapshot has reached SNAPBUILD_CONSISTENT state.
In passing, improve the comments atop ReorderBufferResetTXN to mention the
case when we need to continue streaming after getting an error.
Author: Amit Kapila
Reviewed-by: Dilip Kumar
Discussion: https://postgr.es/m/CAA4eK1KoOH0byboyYY40NBcC7Fe812trwTa+WY3jQF7WQWZbQg@mail.gmail.com
The use of low-level hash routines is not recommended by upstream
OpenSSL since 2000, and pgcrypto already switched to EVP as of 5ff4a67.
This takes advantage of the refactoring done in 87ae969 that has
introduced the allocation and free routines for cryptographic hashes.
Since 1.1.0, OpenSSL does not publish the contents of the cryptohash
contexts, forcing any consumers to rely on OpenSSL for all allocations.
Hence, the resource owner callback mechanism gains a new set of routines
to track and free cryptohash contexts when using OpenSSL, preventing any
risks of leaks in the backend. Nothing is needed in the frontend thanks
to the refactoring of 87ae969, and the resowner knowledge is isolated
into cryptohash_openssl.c.
Note that this also fixes a failure with SCRAM authentication when using
FIPS in OpenSSL, but as there have been few complaints about this
problem and as this causes an ABI breakage, no backpatch is done.
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson, Heikki Linnakangas
Discussion: https://postgr.es/m/20200924025314.GE7405@paquier.xyz
Discussion: https://postgr.es/m/20180911030250.GA27115@paquier.xyz
Two new routines to allocate a hash context and to free it are created,
as these become necessary for the goal behind this refactoring: switch
the all cryptohash implementations for OpenSSL to use EVP (for FIPS and
also because upstream does not recommend the use of low-level cryptohash
functions for 20 years). Note that OpenSSL hides the internals of
cryptohash contexts since 1.1.0, so it is necessary to leave the
allocation to OpenSSL itself, explaining the need for those two new
routines. This part is going to require more work to properly track
hash contexts with resource owners, but this not introduced here.
Still, this refactoring makes the move possible.
This reduces the number of routines for all SHA2 implementations from
twelve (SHA{224,256,386,512} with init, update and final calls) to five
(create, free, init, update and final calls) by incorporating the hash
type directly into the hash context data.
The new cryptohash routines are moved to a new file, called cryptohash.c
for the fallback implementations, with SHA2 specifics becoming a part
internal to src/common/. OpenSSL specifics are part of
cryptohash_openssl.c. This infrastructure is usable for more hash
types, like MD5 or HMAC.
Any code paths using the internal SHA2 routines are adapted to report
correctly errors, which are most of the changes of this commit. The
zones mostly impacted are checksum manifests, libpq and SCRAM.
Note that e21cbb4 was a first attempt to switch SHA2 to EVP, but it
lacked the refactoring needed for libpq, as done here.
This patch has been tested on Linux and Windows, with and without
OpenSSL, and down to 1.0.1, the oldest version supported on HEAD.
Author: Michael Paquier
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/20200924025314.GE7405@paquier.xyz
Tablesync worker runs under a single transaction but in streaming mode, we
were committing the transaction on stream_stop, stream_abort, and
stream_commit. We need to avoid committing the transaction in a streaming
mode in tablesync worker.
In passing move the call to process_syncing_tables in
apply_handle_stream_commit after clean up of stream files. This will
allow clean up of files to happen before the exit of tablesync worker
which would otherwise be handled by one of the proc exit routines.
Author: Dilip Kumar
Reviewed-by: Amit Kapila and Peter Smith
Tested-by: Peter Smith
Discussion: https://postgr.es/m/CAHut+Pt4PyKQCwqzQ=EFF=bpKKJD7XKt_S23F6L20ayQNxg77A@mail.gmail.com
Reverts 27838981be (some comments are kept). Per discussion, it does
not seem safe to relax the lock level used for this; in order for it to
be safe, there would have to be memory barriers between the point we set
the flag and the point we set the trasaction Xid, which perhaps would
not be so bad; but there would also have to be barriers at the readers'
side, which from a performance perspective might be bad.
Now maybe this analysis is wrong and it *is* safe for some reason, but
proof of that is not trivial.
Discussion: https://postgr.es/m/20201118190928.vnztes7c2sldu43a@alap3.anarazel.de
While ereport() and elog() themselves are quite cheap when the
error message level is too low to be printed, some places need to do
substantial work before they can call those macros at all. To allow
optimizing away such setup work when nothing is to be printed, make
elog.c export a new function message_level_is_interesting(elevel)
that reports whether ereport/elog will do anything. Make use of that
in various places that had ad-hoc direct tests of log_min_messages etc.
Also teach ProcSleep to use it to avoid some work. (There may well
be other places that could usefully use this; I didn't search hard.)
Within elog.c, refactor a little bit to avoid having duplicate copies
of the policy-setting logic. When that code was written, we weren't
relying on the availability of inline functions; so it had some
duplications in the name of efficiency, which I got rid of.
Alvaro Herrera and Tom Lane
Discussion: https://postgr.es/m/129515.1606166429@sss.pgh.pa.us
Copy.c has grown really large. Split it into more manageable parts:
- copy.c now contains only a few functions that are common to COPY FROM
and COPY TO.
- copyto.c contains code for COPY TO.
- copyfrom.c contains code for initializing COPY FROM, and inserting the
tuples to the correct table.
- copyfromparse.c contains code for reading from the client/file/program,
and parsing the input text/CSV/binary format into tuples.
All of these parts are fairly complicated, and fairly independent of each
other. There is a patch being discussed to implement parallel COPY FROM,
which will add a lot of new code to the COPY FROM path, and another patch
which would allow INSERTs to use the same multi-insert machinery as COPY
FROM, both of which will require refactoring that code. With those two
patches, there's going to be a lot of code churn in copy.c anyway, so now
seems like a good time to do this refactoring.
The CopyStateData struct is also split. All the formatting options, like
FORMAT, QUOTE, ESCAPE, are put in a new CopyFormatOption struct, which
is used by both COPY FROM and TO. Other state data are kept in separate
CopyFromStateData and CopyToStateData structs.
Reviewed-by: Soumyadeep Chakraborty, Erik Rijkers, Vignesh C, Andres Freund
Discussion: https://www.postgresql.org/message-id/8e15b560-f387-7acc-ac90-763986617bfb%40iki.fi
We don't actually need a lock to set PGPROC->statusFlags itself; what we
do need is a shared lock on either XidGenLock or ProcArrayLock in order to
ensure MyProc->pgxactoff keeps still while we modify the mirror array in
ProcGlobal->statusFlags. Some places were using an exclusive lock for
that, which is excessive. Relax those to use shared lock only.
procarray.c has a couple of places with somewhat brittle assumptions
about PGPROC changes: ProcArrayEndTransaction uses only shared lock, so
it's permissible to change MyProc only. On the other hand,
ProcArrayEndTransactionInternal also changes other procs, so it must
hold exclusive lock. Add asserts to ensure those assumptions continue
to hold.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/20201117155501.GA13805@alvherre.pgsql
In streaming mode, the transaction can be decoded in multiple streams and
those streams can be interleaved with streams of other transactions. So,
we can't remember the transaction's write status in the logical decoding
context because that might get changed due to some other transactions and
lead to wrong answers for 'skip-empty-xacts' option. We decided to keep
each transaction's write status in the ReorderBufferTxn to avoid
interleaved streams changing the status of some unrelated transactions.
Diagnosed-by: Amit Kapila
Author: Dilip Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1LR7=XNM_TLmpZMFuV8ZQpoxkem--NZJYf8YXmesbvwLA@mail.gmail.com
This was marked as BYTEA, but is more like TEXT, which is how we already
pass the history timeline file name. Internally, we don't do any
encoding or bytea escape handling, but TEXT seems closest. This should
cause no behavioral change.
Reported-by: Brar Piening
Discussion: https://postgr.es/m/6a1b9cd9-17e3-df67-be55-86102af6bdf5@gmx.de
Backpatch-through: master
Commit 1e53fe0e70 changed background processes so that they use
standard SIGHUP handler. Like that, this commit makes walreceiver
use standard SIGHUP and SIGTERM handlers, to simplify the code.
As the side effect of this commit, walreceiver can wake up and process
the configuration files promptly when receiving SIGHUP. Because the
standard SIGHUP handler sets the latch. On the other hand, previously
there could be a time lag between the receipt of SIGHUP and
the process of configuration files since the dedicated handler didn't
set the latch.
Author: Bharath Rupireddy, tweaked by Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/CALj2ACXPorUqePswDtOeM_s82v9RW32E1fYmOPZ5NuE+TWKj_A@mail.gmail.com
Attempting to take a base backup with Postgres linking to a build of
OpenSSL with FIPS enabled currently fails with or even without a backup
manifest requested because of this mandatory SHA256 initialization used
for the manifest file itself. However, there is no need to do this
initialization at all if backup manifests are not needed because there
is no data to append to the manifest.
Note that being able to use backup manifests with OpenSSL+FIPS requires
a switch of the SHA2 implementation to use EVP, which would cause an ABI
breakage so this cannot be backpatched to 13 as it has been already
released, but at least avoiding this SHA256 initialization gives users
the possibility to take a base backup even when specifying --no-manifest
with pg_basebackup.
Author: Michael Paquier
Discussion: https://postgr.es/m/20201110020014.GE1887@paquier.xyz
Backpatch-through: 13
Introduce TimestampDifferenceMilliseconds() to simplify callers
that would rather have the difference in milliseconds, instead of
the select()-oriented seconds-and-microseconds format. This gets
rid of at least one integer division per call, and it eliminates
some apparently-easy-to-mess-up arithmetic.
Two of these call sites were in fact wrong:
* pg_prewarm's autoprewarm_main() forgot to multiply the seconds
by 1000, thus ending up with a delay 1000X shorter than intended.
That doesn't quite make it a busy-wait, but close.
* postgres_fdw's pgfdw_get_cleanup_result() thought it needed to compute
microseconds not milliseconds, thus ending up with a delay 1000X longer
than intended. Somebody along the way had noticed this problem but
misdiagnosed the cause, and imposed an ad-hoc 60-second limit rather
than fixing the units. This was relatively harmless in context, because
we don't care that much about exactly how long this delay is; still,
it's wrong.
There are a few more callers of TimestampDifference() that don't
have a direct need for seconds-and-microseconds, but can't use
TimestampDifferenceMilliseconds() either because they do need
microsecond precision or because they might possibly deal with
intervals long enough to overflow 32-bit milliseconds. It might be
worth inventing another API to improve that, but that seems outside
the scope of this patch; so those callers are untouched here.
Given the fact that we are fixing some bugs, and the likelihood
that future patches might want to back-patch code that uses this
new API, back-patch to all supported branches.
Alexey Kondratov and Tom Lane
Discussion: https://postgr.es/m/3b1c053a21c07c1ed5e00be3b2b855ef@postgrespro.ru
Move the system catalog index declarations from catalog/indexing.h to
the respective parent tables' catalog/pg_*.h files. The original
reason for having it split was that the old genbki system produced the
output in the order of the catalog files it read, so all the indexing
stuff needed to come separately. But this is no longer the case, and
keeping it together makes more sense.
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/c7cc82d6-f976-75d6-2e3e-b03d2cab26bb@2ndquadrant.com
Logical replication protocol uses a single byte character to identify a
message type in logical replication protocol. The code uses string
literals for the same. Use Enum so that
1. All the string literals used can be found at a single place. This
makes it easy to add more types without the risk of conflicts.
2. It's easy to locate the code handling a given message type.
3. When used with switch statements, it is easy to identify the missing
cases using -Wswitch.
Author: Ashutosh Bapat
Reviewed-by: Kyotaro Horiguchi, Andres Freund, Peter Smith and Amit Kapila
Discussion: https://postgr.es/m/CAExHW5uPzQ7L0oAd_ENyvaiYMOPgkrAoJpE+ZY5-obdcVT6NPg@mail.gmail.com
This adds the statistics about transactions streamed to the decoding
output plugin from ReorderBuffer. Users can query the
pg_stat_replication_slots view to check these stats and call
pg_stat_reset_replication_slot to reset the stats of a particular slot.
Users can pass NULL in pg_stat_reset_replication_slot to reset stats of
all the slots.
Commit 9868167500 has added the basic infrastructure to capture the stats
of slot and this commit extends the statistics collector to track
additional information about slots.
Bump the catversion as we have added new columns in the catalog entry.
Author: Ajin Cherian and Amit Kapila
Reviewed-by: Sawada Masahiko and Dilip Kumar
Discussion: https://postgr.es/m/CAA4eK1+chpEomLzgSoky-D31qev19AmECNiEAietPQUGEFhtVA@mail.gmail.com
It's unsafe to do this at parse time because addition of generated
columns to a table would not invalidate stored rules containing
UPDATEs on the table ... but there might now be dependent generated
columns that were not there when the rule was made. This also fixes
an oversight that rewriteTargetView failed to update extraUpdatedCols
when transforming an UPDATE on an updatable view. (Since the new
calculation is downstream of that, rewriteTargetView doesn't actually
need to do anything; but before, there was a demonstrable bug there.)
In v13 and HEAD, this leads to easily-visible bugs because (since
commit c6679e4fc) we won't recalculate generated columns that aren't
listed in extraUpdatedCols. In v12 this bitmap is mostly just used
for trigger-firing decisions, so you'd only notice a problem if a
trigger cared whether a generated column had been updated.
I'd complained about this back in May, but then forgot about it
until bug #16671 from Michael Paul Killian revived the issue.
Back-patch to v12 where this field was introduced. If existing
stored rules contain any extraUpdatedCols values, they'll be
ignored because the rewriter will overwrite them, so the bug will
be fixed even for existing rules. (But note that if someone were
to update to 13.1 or 12.5, store some rules with UPDATEs on tables
having generated columns, and then downgrade to a prior minor version,
they might observe issues similar to what this patch fixes. That
seems unlikely enough to not be worth going to a lot of effort to fix.)
Discussion: https://postgr.es/m/10206.1588964727@sss.pgh.pa.us
Discussion: https://postgr.es/m/16671-2fa55851859fb166@postgresql.org
Most importantly, remove optimization in LogicalRepSyncTableStart that
skips the normal walrcv_startstreaming/endstreaming dance. The
optimization is not critically important for production uses anyway,
since it only fires in cases with no activity, and saves an
uninteresting amount of work even then. Critically, it obscures bugs by
hiding the interesting code path from test cases.
Also: in GetSubscriptionRelState, remove pointless relation open; access
pg_subscription_rel->srsubstate with GETSTRUCT as is typical rather than
SysCacheGetAttr; remove unused 'missing_ok' argument.
In wait_for_relation_state_change, use explicit catalog snapshot
invalidation rather than obscurely (and expensively) through
GetLatestSnapshot.
In various places: sprinkle comments more liberally and rewrite a number
of them. Other cosmetic code improvements.
No backpatch, since no bug is being fixed here.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Petr Jelínek <petr.jelinek@2ndquadrant.com>
Discussion: https://postgr.es/m/20201010190637.GA5774@alvherre.pgsql
A number of places were using appendStringInfo() when they could have been
using appendStringInfoString() instead. While there's no functionality
change there, it's just more efficient to use appendStringInfoString()
when no formatting is required. Likewise for some
appendStringInfoString() calls which were just appending a single char.
We can just use appendStringInfoChar() for that.
Additionally, many places were using appendPQExpBuffer() when they could
have used appendPQExpBufferStr(). Change those too.
Patch by Zhijie Hou, but further searching by me found significantly more
places that deserved the same treatment.
Author: Zhijie Hou, David Rowley
Discussion: https://postgr.es/m/cb172cf4361e4c7ba7167429070979d4@G08CNEXMBPEKD05.g08.fujitsu.local
during logical decoding.
Prior to commit c55040ccd0 we have no way of knowing the invalidations
before commit. So, while decoding we use to execute all the invalidations
at each command end as we had no way of knowing which invalidations
happened before that command. Due to this, transactions involving large
amounts of DDLs use to take more time and also lead to high CPU usage. But
now we know specific invalidations at each command end so we execute only
required invalidations.
It has been observed that decoding of a transaction containing truncation
of a table with 1000 partitions would be finished in 1s whereas before
this patch it used to take 4-5 minutes.
Author: Dilip Kumar
Reviewed-by: Amit Kapila and Keisuke Kuroda
Discussion: https://postgr.es/m/CANDwggKYveEtXjXjqHA6RL3AKSHMsQyfRY6bK+NqhAWJyw8psQ@mail.gmail.com
I removed the duplicate command tags for START_REPLICATION inadvertently
in commit 07082b08cc, but the replication protocol requires them. The
fact that the replication protocol was broken was not noticed because
all our test cases use an optimized code path that exits early, failing
to verify that the behavior is correct for non-optimized cases. Put
them back.
Also document this protocol quirk.
Add a test case that shows the failure. It might still succeed even
without the patch when run on a fast enough server, but it suffices to
show the bug in enough cases that it would be noticed in buildfarm.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Henry Hinze <henry.hinze@gmail.com>
Reviewed-by: Petr Jelínek <petr.jelinek@2ndquadrant.com>
Discussion: https://postgr.es/m/16643-eaadeb2a1a58d28c@postgresql.org
Maintaining 'es_result_relation_info' correctly at all times has become
cumbersome, especially with partitioning where each partition gets its
own result relation info. Having to set and reset it across arbitrary
operations has caused bugs in the past.
This changes all the places that used 'es_result_relation_info', to
receive the currently active ResultRelInfo via function parameters
instead.
Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
Instead of allocating all the ResultRelInfos upfront in one big array,
allocate them in ExecInitModifyTable(). es_result_relations is now an
array of ResultRelInfo pointers, rather than an array of structs, and it
is indexed by the RT index.
This simplifies things: we get rid of the separate concept of a "result
rel index", and don't need to set it in setrefs.c anymore. This also
allows follow-up optimizations (not included in this commit yet) to skip
initializing ResultRelInfos for target relations that were not needed at
runtime, and removal of the es_result_relation_info pointer.
The EState arrays of regular result rels and root result rels are merged
into one array. Similarly, the resultRelations and rootResultRelations
lists in PlannedStmt are merged into one. It's not actually clear to me
why they were kept separate in the first place, but now that the
es_result_relations array is indexed by RT index, it certainly seems
pointless.
The PlannedStmt->resultRelations list is now only needed for
ExecRelationIsTargetRelation(). One visible effect of this change is that
ExecRelationIsTargetRelation() will now return 'true' also for the
partition root, if a partitioned table is updated. That seems like a good
thing, although the function isn't used in core code, and I don't see any
reason for an FDW to call it on a partition root.
Author: Amit Langote
Discussion: https://www.postgresql.org/message-id/CA%2BHiwqGEmiib8FLiHMhKB%2BCH5dRgHSLc5N5wnvc4kym%2BZYpQEQ%40mail.gmail.com
This adds the statistics about transactions spilled to disk from
ReorderBuffer. Users can query the pg_stat_replication_slots view to check
these stats and call pg_stat_reset_replication_slot to reset the stats of
a particular slot. Users can pass NULL in pg_stat_reset_replication_slot
to reset stats of all the slots.
This commit extends the statistics collector to track this information
about slots.
Author: Sawada Masahiko and Amit Kapila
Reviewed-by: Amit Kapila and Dilip Kumar
Discussion: https://postgr.es/m/CA+fd4k5_pPAYRTDrO2PbtTOe0eHQpBvuqmCr8ic39uTNmR49Eg@mail.gmail.com
In logical replication when a subscriber is missing some columns, it
currently emits an error message that says "some" columns are missing, but
it doesn't specify the missing column names. Change that to display
missing column names which makes an error to be more informative to the
user.
We have decided not to backpatch this commit as this is a minor usability
improvement and no user has reported this.
Reported-by: Bharath Rupireddy
Author: Bharath Rupireddy
Reviewed-by: Kyotaro Horiguchi and Amit Kapila
Discussion: https://postgr.es/m/CALj2ACVkW-EXH_4pmBK8tNeHRz5ksUC4WddGactuCjPiBch-cg@mail.gmail.com
Previously the standby server didn't archive timeline history files
streamed from the primary even when archive_mode is set to "always",
while it archives the streamed WAL files. This could cause the PITR to
fail because there was no required timeline history file in the archive.
The cause of this issue was that walreceiver didn't mark those files as
ready for archiving.
This commit makes walreceiver mark those streamed timeline history
files as ready for archiving if archive_mode=always. Then the archiver
process archives the marked timeline history files.
Back-patch to all supported versions.
Reported-by: Grigory Smolkin
Author: Grigory Smolkin, Fujii Masao
Reviewed-by: David Zhang, Anastasia Lubennikova
Discussion: https://postgr.es/m/54b059d4-2b48-13a4-6f43-95a087c92367@postgrespro.ru
Commit 464824323e changed the logical replication protocol to allow the
streaming of in-progress transactions and used the new version of protocol
irrespective of the server version. Use the appropriate version of the
protocol based on the server version.
Reported-by: Ashutosh Sharma
Author: Dilip Kumar
Reviewed-by: Ashutosh Sharma and Amit Kapila
Discussion: https://postgr.es/m/CAE9k0P=9OpXcNrcU5Gsvd5MZ8GFpiN833vNHzX6Uc=8+h1ft1Q@mail.gmail.com
Because the code path taken for SQL commands executed in a walsender
will update the process title, we pretty much have to update the
title for replication commands as well. Otherwise, the title shows
"idle" for the rest of a logical walsender's lifetime once it's
executed any SQL command.
Playing with this, I confirm that a walsender now typically spends
most of its life reporting
walsender postgres [local] START_REPLICATION
Considering this in isolation, it might be better to have it say
walsender postgres [local] sending replication data
However, consistency with the other cases seems to be a stronger
argument.
In passing, remove duplicative pgstat_report_activity call.
Discussion: https://postgr.es/m/880181.1600026471@sss.pgh.pa.us
Since commit fd5942c18f (2012, 9.3-era), walsender has been sending
completion tags for certain replication commands twice -- and they're
not even consistent. Apparently neither libpq nor JDBC have a problem
with it, but it's not kosher. Fix by remove the EndCommand() call in
the common code path for them all, and inserting specific calls to
EndReplicationCommand() specifically in those places where it's needed.
EndReplicationCommand() is a new simple function to send the completion
tag for replication commands. Do this instead of sending a generic
SELECT completion tag for them all, which was also pretty bogus (if
innocuous). While at it, change StartReplication() to use
EndReplicationCommand() instead of pg_puttextmessage().
In commit 2f9661311b, I failed to realize that replication commands
are not close-enough kin of regular SQL commands, so the
DROP_REPLICATION_SLOT tag I added is undeserved and a type pun. Take it
out.
Backpatch to 13, where the latter commit appeared. The duplicate tag
has been sent since 9.3, but since nothing is broken, it doesn't seem
worth fixing.
Per complaints from Tom Lane.
Discussion: https://postgr.es/m/1347966.1600195735@sss.pgh.pa.us
We decided that the policy established in commit 7634bd4f6 for
the bgwriter, checkpointer, walwriter, and walreceiver processes,
namely that they should accept SIGQUIT at all times, really ought
to apply uniformly to all postmaster children. Therefore, get
rid of the duplicative and inconsistent per-process code for
establishing that signal handler and removing SIGQUIT from BlockSig.
Instead, make InitPostmasterChild do it.
The handler set up by InitPostmasterChild is SignalHandlerForCrashExit,
which just summarily does _exit(2). In interactive backends, we
almost immediately replace that with quickdie, since we would prefer
to try to tell the client that we're dying. However, this patch is
changing the behavior of autovacuum (both launcher and workers), as
well as walsenders. Those processes formerly also used quickdie,
but AFAICS that was just mindless copy-and-paste: they don't have
any interactive client that's likely to benefit from being told this.
The stats collector continues to be an outlier, in that it thinks
SIGQUIT means normal exit. That should probably be changed for
consistency, but there's another patch set where that's being
dealt with, so I didn't do so here.
Discussion: https://postgr.es/m/644875.1599933441@sss.pgh.pa.us
Since there is only one place that actually needs the partition check
expression, namely ExecPartitionCheck, it's better to fetch it from
the relcache there. In this way we will never fetch it at all if
the query never has use for it, and we still fetch it just once when
we do need it.
The reason for taking an interest in this is that if the relcache
doesn't already have the check expression cached, fetching it
requires obtaining AccessShareLock on the partition root. That
means that operations that look like they should only touch the
partition itself will also take a lock on the root. In particular
we observed that TRUNCATE on a partition may take a lock on the
partition's root, contributing to a deadlock situation in parallel
pg_restore.
As written, this patch does have a small cost, which is that we
are microscopically reducing efficiency for the case where a partition
has an empty check expression. ExecPartitionCheck will be called,
and will go through the motions of setting up and checking an empty
qual, where before it would not have been called at all. We could
avoid that by adding a separate boolean flag to track whether there
is a partition expression to test. However, this case only arises
for a default partition with no siblings, which surely is not an
interesting case in practice. Hence adding complexity for it
does not seem like a good trade-off.
Amit Langote, per a suggestion by me
Discussion: https://postgr.es/m/VI1PR03MB31670CA1BD9625C3A8C5DD05EB230@VI1PR03MB3167.eurprd03.prod.outlook.com
The code recorded cache invalidation events by zeroing the "localreloid"
field of affected cache entries. However, it's possible for an inval
event to occur even while we have the entry open and locked. So an
ill-timed inval could result in "cache lookup failed for relation 0"
errors, if the worker's code tried to use the cleared field. We can
fix that by creating a separate bool field to record whether the entry
needs to be revalidated. (In the back branches, cram the bool into
what had been padding space, to avoid an ABI break in the somewhat
unlikely event that any extension is looking at this struct.)
Also, rearrange the logic in logicalrep_rel_open so that it
does the right thing in cases where table_open would fail.
We should retry the lookup by name in that case, but we didn't.
The real-world impact of this is probably small. In the first place,
the error conditions are very low probability, and in the second place,
the worker would just exit and get restarted. We only noticed because
in a CLOBBER_CACHE_ALWAYS build, the failure can occur repeatedly,
preventing the worker from making progress. Nonetheless, it's clearly
a bug, and it impedes a useful type of testing; so back-patch to v10
where this code was introduced.
Discussion: https://postgr.es/m/1032727.1600096803@sss.pgh.pa.us
In commit 464824323e, for each RelationSyncEntry we maintained the list
of xids (streamed_txns) for which we have already sent the schema. This
helps us to track when to send the schema to the downstream node for
replication of streaming transactions. Before this list got initialized,
we were processing invalidation messages which access this list and led
to an assertion failure.
In passing, clean up the nearby code:
* Initialize the list of xids with NIL instead of NULL which is our usual
coding practice.
* Remove the MemoryContext switch for creating a RelationSyncEntry in dynahash.
Diagnosed-by: Amit Kapila and Tom Lane
Author: Amit Kapila
Reviewed-by: Tom Lane and Dilip Kumar
Discussion: https://postgr.es/m/904373.1600033123@sss.pgh.pa.us
A walsender process that has executed a SQL command left the text of
that command in pg_stat_activity.query indefinitely, which is quite
confusing if it's in RUNNING state but not doing that query. An easy
and useful fix is to treat replication commands as if they were SQL
queries, and show them in pg_stat_activity according to the same rules
as for regular queries. While we're at it, it seems also sensible to
set debug_query_string, allowing error logging and debugging to see
the replication command.
While here, clean up assorted silliness in exec_replication_command:
* The SQLCmd path failed to restore CurrentMemoryContext to the caller's
value, and failed to delete the temp context created in this routine.
It's only through great good fortune that these oversights did not
result in long-term memory leaks or other problems. It seems cleaner
to code SQLCmd as a separate early-exit path, so do it like that.
* Remove useless duplicate call of SnapBuildClearExportedSnapshot().
* replication_scanner_finish() was never called.
None of those things are significant enough to merit a backpatch,
so this is for HEAD only.
Discussion: https://postgr.es/m/880181.1600026471@sss.pgh.pa.us
The bgwriter, checkpointer, walwriter, and walreceiver processes
claimed to allow SIGQUIT "at all times". In reality SIGQUIT
would get re-blocked during error recovery, because we didn't
update the actual signal mask immediately, so sigsetjmp() would
save and reinstate a mask that includes SIGQUIT.
This appears to be simply a coding oversight. There's never a
good reason to hold off SIGQUIT in these processes, because it's
going to just call _exit(2) which should be safe enough, especially
since the postmaster is going to tear down shared memory afterwards.
Hence, stick in PG_SETMASK() calls to install the modified BlockSig
mask immediately.
Also try to improve the comments around sigsetjmp blocks. Most of
them were just referencing postgres.c, which is misleading because
actually postgres.c manages the signals differently.
No back-patch, since there's no evidence that this is causing any
problems in the field.
Discussion: https://postgr.es/m/CALDaNm1d1hHPZUg3xU4XjtWBOLCrA+-2cJcLpw-cePZ=GgDVfA@mail.gmail.com
Tomas Vondra
Robert Haas
Amit Kapila
Michael Paquier
Andres Freund
Heikki Linnakangas
Peter Eisentraut
Tom Lane
Alvaro Herrera
Jeff Davis
Bruce Momjian
Fujii Masao
Daniel Gustafsson
Noah Misch
Andrew Dunstan
Thomas Munro
Peter Geoghegan
Stephen Frost
David Rowley