Commit Graph

339 Commits

Author SHA1 Message Date
Amit Kapila 5de94a041e Add 'logical_decoding_mode' GUC.
This enables streaming or serializing changes immediately in logical
decoding. This parameter is intended to be used to test logical decoding
and replication of large transactions for which otherwise we need to
generate the changes till logical_decoding_work_mem is reached.

This helps in reducing the timing of existing tests related to logical
replication of in-progress transactions and will help in writing tests for
for the upcoming feature for parallelly applying large in-progress
transactions.

Author: Shi yu
Reviewed-by: Sawada Masahiko, Shveta Mallik, Amit Kapila, Dilip Kumar, Kuroda Hayato, Kyotaro Horiguchi
Discussion: https://postgr.es/m/OSZPR01MB63104E7449DBE41932DB19F1FD1B9@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-12-26 08:58:16 +05:30
Amit Kapila bf07ab492c Avoid unnecessary streaming of transactions during logical replication.
After restart, we don't perform streaming of an in-progress transaction if
it was previously decoded and confirmed by the client. To achieve that we
were comparing the END location of the WAL record being decoded with the
WAL location we have already decoded and confirmed by the client. While
decoding the commit record, to decide whether to process and send the
complete transaction, we compare its START location with the WAL location
we have already decoded and confirmed by the client. Now, if we need to
queue some change in the transaction while decoding the commit record
(e.g. snapshot), it is possible that we decide to stream the transaction
but later commit processing decides to skip it. In such a case, we would
needlessly send the changes and later when we decide to skip it, we will
send stream abort.

We also sometimes decide to stream the changes when we actually just need
to process them locally like a change for invalidations. This will lead us
to send empty streams. To avoid this, while queuing each change for
decoding, we remember whether the transaction has any change that actually
needs to be sent downstream and use that information later to decide
whether to stream the transaction or not.

Note, we can't avoid all cases where we have to send empty streams like
the case where the plugin later decides that the change is not
publishable. However, we will no longer need to send stream_abort when we
skip sending a particular transaction.

Author: Dilip Kumar
Reviewed-by: Hou Zhijie, Ashutosh Bapat, Shi yu, Amit Kapila
Discussion: https://postgr.es/m/CAFiTN-tHK=7LzfrPs8fbT2ksrOJGQbzywcgXst2bM9-rJJAAUg@mail.gmail.com
2022-12-08 06:05:09 +05:30
Amit Kapila 40b1491357 Fix incorrect output from pgoutput when using column lists.
For Updates and Deletes, we were not honoring the columns list for old
tuple values while sending tuple data via pgoutput. This results in
pgoutput emitting more columns than expected.

This is not a problem for built-in logical replication as we simply ignore
additional columns based on the relation information sent previously which
didn't have those columns. However, some other users of pgoutput plugin
may expect the columns as per the column list. Also, sending extra columns
unnecessarily consumes network bandwidth defeating the purpose of the
column list feature.

Reported-by: Gunnar Morling
Author: Hou Zhijie
Reviewed-by: Amit Kapila
Backpatch-through: 15
Discussion: https://postgr.es/m/CADGJaX9kiRZ-OH0EpWF5Fkyh1ZZYofoNRCrhapBfdk02tj5EKg@mail.gmail.com
2022-12-02 10:52:58 +05:30
David Rowley 7c335b7a20 Add doubly linked count list implementation
We have various requirements when using a dlist_head to keep track of the
number of items in the list.  This, traditionally, has been done by
maintaining a counter variable in the calling code.  Here we tidy this up
by adding "dclist", which is very similar to dlist but also keeps track of
the number of items stored in the list.

Callers may use the new dclist_count() function when they need to know how
many items are stored. Obtaining the count is an O(1) operation.

For simplicity reasons, dclist and dlist both use dlist_node as their node
type and dlist_iter/dlist_mutable_iter as their iterator type. dclists
have all of the same functionality as dlists except there is no function
named dclist_delete().  To remove an item from a list dclist_delete_from()
must be used.  This requires knowing which dclist the given item is stored
in.

Additionally, here we also convert some dlists where additional code
exists to keep track of the number of items stored and to make these use
dclists instead.

Author: David Rowley
Reviewed-by: Bharath Rupireddy, Aleksander Alekseev
Discussion: https://postgr.es/m/CAApHDvrtVxr+FXEX0VbViCFKDGxA3tWDgw9oFewNXCJMmwLjLg@mail.gmail.com
2022-11-02 14:06:05 +13:00
Amit Kapila 776e1c8a5d Add a common function to generate the origin name.
Make a common replication origin name formatting function to replace
multiple snprintf() expressions. This also includes logic previously done
by ReplicationOriginNameForTablesync().

This makes the code to generate the origin name consistent among apply
worker and tablesync worker.

Author: Peter Smith
Reviewed-By: Aleksander Alekseev
Discussion: https://postgr.es/m/CAHut%2BPsa8hhfSE6ozUK-ih7GkQziAVAf4f3bqiXEj2nQiu-43g%40mail.gmail.com
2022-10-11 10:37:52 +05:30
Andres Freund 06dbd619bf pgstat: Prevent stats reset from corrupting slotname by removing slotname
Previously PgStat_StatReplSlotEntry contained the slotname, which was mainly
used when writing out the stats during shutdown, to identify the slot in the
serialized data (at runtime the index in ReplicationSlotCtl->replication_slots
is used, but that can change during a restart). Unfortunately the slotname was
overwritten when the slot's stats were reset.

That turned out to only cause "real" problems if the slot was active during
the reset, triggering an assertion failure at the next
pgstat_report_replslot(). In other paths the stats were re-initialized during
pgstat_acquire_replslot().

Fix this by removing slotname from PgStat_StatReplSlotEntry. Instead we can
get the slot's name from the slot itself. Besides fixing a bug, this also is
architecturally cleaner (a name is not really statistics). This is safe
because stats, for a slot removed while shut down, will not be restored at
startup.

In 15 the slotname is not removed, but renamed, to avoid changing the stats
format. In master, bump PGSTAT_FILE_FORMAT_ID.

This commit does not contain a test for the fix. I think this can only be
tested by a tap test starting pg_recvlogical in the background and checking
pg_recvlogical's output. That type of test is notoriously hard to be reliable,
so committing it shortly before the release is wrapped seems like a bad idea.

Reported-by: Jaime Casanova <jcasanov@systemguards.com.ec>
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/YxfagaTXUNa9ggLb@ahch-to
Backpatch: 15-, where the bug was introduced in 5891c7a8ed
2022-10-08 09:43:29 -07:00
Amit Kapila af51b2f042 Remove unused xid parameter.
Commit 6c2003f8a1 removes the use of transaction id's for exporting
snapshots. This commit removes one unused xid parameter left behind in
SnapBuildGetOrBuildSnapshot.

Author: Melih Mutlu
Reviewed-By: Zhang Mingli
Discussion: https://postgr.es/m/CAGPVpCTqZRoDKgCycw+eYi+Gq41rN9pU-gntgTd7wfsNDpPL3Q@mail.gmail.com
2022-09-26 08:47:00 +05:30
Peter Geoghegan 8fb4e001e9 Harmonize more lexer function parameter names.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions for several "lexer
adjacent" backend functions.  These were missed by commit aab06442.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-22 13:27:16 -07:00
Peter Geoghegan aab06442d4 Harmonize lexer adjacent function parameter names.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions for several "lexer
adjacent" backend functions.

These functions were missed by recent commits because they were obscured
by clang-tidy warnings about functions whose signature is directly under
the control of the lexer (flex seems to always generate function
declarations with unnamed parameters).  We probably can't fix most of
the warnings it generates for translation units that get built from .l
and .y files, but we can at least do this much.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-21 13:21:36 -07:00
Amit Kapila a932824dfe Pass Size as a 2nd argument for snprintf() in tablesync.c.
Previously the following snprintf() wrappers:

* ReplicationSlotNameForTablesync()
* ReplicationOriginNameForTablesync()

... used int as a second argument of snprintf() while the actual type of it
is size_t. Although it doesn't fail at present better replace it with Size
for consistency with the rest of the system.

Author: Aleksander Alekseev
Reviewed-By: Peter Smith
Discussion: https://postgr.es/m/CAHut%2BPsa8hhfSE6ozUK-ih7GkQziAVAf4f3bqiXEj2nQiu-43g%40mail.gmail.com
2022-09-21 10:20:37 +05:30
Peter Geoghegan bfcf1b3480 Harmonize parameter names in storage and AM code.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in storage, catalog,
access method, executor, and logical replication code, as well as in
miscellaneous utility/library code.

Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy.  Later commits will do the
same for other parts of the codebase.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-19 19:18:36 -07:00
Peter Geoghegan 4bac9600f0 Harmonize heapam and tableam parameter names.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions.  Having parameter names
that are reliably consistent in this way will make it easier to reason
about groups of related C functions from the same translation unit as a
module.  It will also make certain refactoring tasks easier.

Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy.  Later commits will do the
same for other parts of the codebase.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
2022-09-19 16:46:23 -07:00
Peter Geoghegan f66d997fd0 Harmonize missed reorderbuffer parameter names.
The function ReorderBufferCommitChild() was overlooked by initial work
from commit 035ce1fe.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkhzFESnRo+VaGqyEZuzc33Dw09BdZBVmW896Sa22ci_A@mail.gmail.com
2022-09-18 12:05:07 -07:00
Peter Geoghegan 035ce1feb2 Harmonize reorderbuffer parameter names.
Make reorderbuffer.h function declarations consistently use named
parameters.  Also make sure that the declarations use names that match
corresponding names from function definitions in reorderbuffer.c.  This
makes the definitions easier to follow, especially in the case of
functions that happen to have adjoining arguments of the same type.

This patch was written with help from clang-tidy.  Specifically, its
"readability-inconsistent-declaration-parameter-name" check and its
"readability-named-parameter" check were used.

Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/3955318.1663377656@sss.pgh.pa.us
2022-09-17 17:20:17 -07:00
Tom Lane 0a20ff54f5 Split up guc.c for better build speed and ease of maintenance.
guc.c has grown to be one of our largest .c files, making it
a bottleneck for compilation.  It's also acquired a bunch of
knowledge that'd be better kept elsewhere, because of our not
very good habit of putting variable-specific check hooks here.
Hence, split it up along these lines:

* guc.c itself retains just the core GUC housekeeping mechanisms.
* New file guc_funcs.c contains the SET/SHOW interfaces and some
  SQL-accessible functions for GUC manipulation.
* New file guc_tables.c contains the data arrays that define the
  built-in GUC variables, along with some already-exported constant
  tables.
* GUC check/assign/show hook functions are moved to the variable's
  home module, whenever that's clearly identifiable.  A few hard-
  to-classify hooks ended up in commands/variable.c, which was
  already a home for miscellaneous GUC hook functions.

To avoid cluttering a lot more header files with #include "guc.h",
I also invented a new header file utils/guc_hooks.h and put all
the GUC hook functions' declarations there, regardless of their
originating module.  That allowed removal of #include "guc.h"
from some existing headers.  The fallout from that (hopefully
all caught here) demonstrates clearly why such inclusions are
best minimized: there are a lot of files that, for example,
were getting array.h at two or more levels of remove, despite
not having any connection at all to GUCs in themselves.

There is some very minor code beautification here, such as
renaming a couple of inconsistently-named hook functions
and improving some comments.  But mostly this just moves
code from point A to point B and deals with the ensuing
needs for #include adjustments and exporting a few functions
that previously weren't exported.

Patch by me, per a suggestion from Andres Freund; thanks also
to Michael Paquier for the idea to invent guc_funcs.c.

Discussion: https://postgr.es/m/587607.1662836699@sss.pgh.pa.us
2022-09-13 11:11:45 -04:00
Michael Paquier 49e525a08f Fix comment in walsender_private.h
All the members of the stucture are protected by the spinlock WalSnd,
but a comment referred to "replyTime" and "latch" as not being in the
set of what gets protected, contrary to what walsender.c does.

Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACWE_7srye4_GZ=N=-rD=qr2WHL9GZrMnhWJOJ5RdnNS2A@mail.gmail.com
2022-08-22 10:02:53 +09:00
Thomas Munro 5579388d2d Remove replacement code for getaddrinfo.
SUSv3, all targeted Unixes and modern Windows have getaddrinfo() and
related interfaces.  Drop the replacement implementation, and adjust
some headers slightly to make sure that the APIs are visible everywhere
using standard POSIX headers and names.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKG%2BL_3brvh%3D8e0BW_VfX9h7MtwgN%3DnFHP5o7X2oZucY9dg%40mail.gmail.com
2022-08-14 09:53:28 +12:00
Amit Kapila 7f13ac8123 Fix catalog lookup with the wrong snapshot during logical decoding.
Previously, we relied on HEAP2_NEW_CID records and XACT_INVALIDATION
records to know if the transaction has modified the catalog, and that
information is not serialized to snapshot. Therefore, after the restart,
if the logical decoding decodes only the commit record of the transaction
that has actually modified a catalog, we will miss adding its XID to the
snapshot. Thus, we will end up looking at catalogs with the wrong
snapshot.

To fix this problem, this change adds the list of transaction IDs and
sub-transaction IDs, that have modified catalogs and are running during
snapshot serialization, to the serialized snapshot. After restart or
otherwise, when we restore from such a serialized snapshot, the
corresponding list is restored in memory. Now, when decoding a COMMIT
record, we check both the list and the ReorderBuffer to see if the
transaction has modified catalogs.

Since this adds additional information to the serialized snapshot, we
cannot backpatch it. For back branches, we took another approach.
We remember the last-running-xacts list of the decoded RUNNING_XACTS
record after restoring the previously serialized snapshot. Then, we mark
the transaction as containing catalog changes if it's in the list of
initial running transactions and its commit record has
XACT_XINFO_HAS_INVALS. This doesn't require any file format changes but
the transaction will end up being added to the snapshot even if it has
only relcache invalidations. But that won't be a problem since we use
snapshot built during decoding only to read system catalogs.

This commit bumps SNAPBUILD_VERSION because of a change in SnapBuild.

Reported-by: Mike Oh
Author: Masahiko Sawada
Reviewed-by: Amit Kapila, Shi yu, Takamichi Osumi, Kyotaro Horiguchi, Bertrand Drouvot, Ahsan Hadi
Backpatch-through: 10
Discussion: https://postgr.es/m/81D0D8B0-E7C4-4999-B616-1E5004DBDCD2%40amazon.com
2022-08-11 10:09:24 +05:30
Robert Haas a8c0128697 Move basebackup code to new directory src/backend/backup
Reviewed by David Steele and Justin Pryzby

Discussion: http://postgr.es/m/CA+TgmoafqboATDSoXHz8VLrSwK_MDhjthK4hEpYjqf9_1Fmczw%40mail.gmail.com
2022-08-10 14:03:23 -04:00
John Naylor bcabbfc6a9 Fix formatting and comment typos
Justin Pryzby

Discussion: https://www.postgresql.org/message-id/20220801181136.GJ15006%40telsasoft.com
2022-08-04 16:41:29 +07:00
Michael Paquier 245e14e28b Fix inconsistent comments for some function declarations in headers
Some of the headers list a couple of function prototypes located in a
different file than what is referred to.  This fixes a couple of
places where this inconsistency exists.

Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4__RdcSNXPa7L62Ozvo_Q4LvT60o3Bnp8yrQ_m9y5CKvg@mail.gmail.com
2022-08-04 17:36:21 +09:00
Amit Kapila 366283961a Allow users to skip logical replication of data having origin.
This patch adds a new SUBSCRIPTION parameter "origin". It specifies
whether the subscription will request the publisher to only send changes
that don't have an origin or send changes regardless of origin. Setting it
to "none" means that the subscription will request the publisher to only
send changes that have no origin associated. Setting it to "any" means
that the publisher sends changes regardless of their origin. The default
is "any".
Usage:
CREATE SUBSCRIPTION sub1 CONNECTION 'dbname=postgres port=9999'
PUBLICATION pub1 WITH (origin = none);

This can be used to avoid loops (infinite replication of the same data)
among replication nodes.

This feature allows filtering only the replication data originating from
WAL but for initial sync (initial copy of table data) we don't have such a
facility as we can only distinguish the data based on origin from WAL. As
a follow-up patch, we are planning to forbid the initial sync if the
origin is specified as none and we notice that the publication tables were
also replicated from other publishers to avoid duplicate data or loops.

We forbid to allow creating origin with names 'none' and 'any' to avoid
confusion with the same name options.

Author: Vignesh C, Amit Kapila
Reviewed-By: Peter Smith, Amit Kapila, Dilip Kumar, Shi yu, Ashutosh Bapat, Hayato Kuroda
Discussion: https://postgr.es/m/CALDaNm0gwjY_4HFxvvty01BOT01q_fJLKQ3pWP9=9orqubhjcQ@mail.gmail.com
2022-07-21 08:47:38 +05:30
Andres Freund f2b73c8d75 Add central declarations for dlsym()ed symbols
This is in preparation for defaulting to -fvisibility=hidden in extensions,
instead of exporting all symbols. For that symbols intended to be exported
need to be tagged with PGDLLEXPORT. Most extensions only need to do so for
_PG_init() and functions defined with PG_FUNCTION_INFO_V1. Adding central
declarations avoids each extension having to add PGDLLEXPORT. Any existing
declarations in extensions will continue to work if fmgr.h is included before
them, otherwise compilation for Windows will fail.

Author: Andres Freund <andres@anarazel.de>
Reviewed-By: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20211101020311.av6hphdl6xbjbuif@alap3.anarazel.de
2022-07-17 17:23:42 -07:00
Robert Haas b0a55e4329 Change internal RelFileNode references to RelFileNumber or RelFileLocator.
We have been using the term RelFileNode to refer to either (1) the
integer that is used to name the sequence of files for a certain relation
within the directory set aside for that tablespace/database combination;
or (2) that value plus the OIDs of the tablespace and database; or
occasionally (3) the whole series of files created for a relation
based on those values. Using the same name for more than one thing is
confusing.

Replace RelFileNode with RelFileNumber when we're talking about just the
single number, i.e. (1) from above, and with RelFileLocator when we're
talking about all the things that are needed to locate a relation's files
on disk, i.e. (2) from above. In the places where we refer to (3) as
a relfilenode, instead refer to "relation storage".

Since there is a ton of SQL code in the world that knows about
pg_class.relfilenode, don't change the name of that column, or of other
SQL-facing things that derive their name from it.

On the other hand, do adjust closely-related internal terminology. For
example, the structure member names dbNode and spcNode appear to be
derived from the fact that the structure itself was called RelFileNode,
so change those to dbOid and spcOid. Likewise, various variables with
names like rnode and relnode get renamed appropriately, according to
how they're being used in context.

Hopefully, this is clearer than before. It is also preparation for
future patches that intend to widen the relfilenumber fields from its
current width of 32 bits. Variables that store a relfilenumber are now
declared as type RelFileNumber rather than type Oid; right now, these
are the same, but that can now more easily be changed.

Dilip Kumar, per an idea from me. Reviewed also by Andres Freund.
I fixed some whitespace issues, changed a couple of words in a
comment, and made one other minor correction.

Discussion: http://postgr.es/m/CA+TgmoamOtXbVAQf9hWFzonUo6bhhjS6toZQd7HZ-pmojtAmag@mail.gmail.com
Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com
Discussion: http://postgr.es/m/CAFiTN-vTe79M8uDH1yprOU64MNFE+R3ODRuA+JWf27JbhY4hJw@mail.gmail.com
2022-07-06 11:39:09 -04:00
Amit Kapila b7658c24c7 Fix data inconsistency between publisher and subscriber.
We were not updating the partition map cache in the subscriber even when
the corresponding remote rel is changed. Due to this data was getting
incorrectly replicated for partition tables after the publisher has
changed the table schema.

Fix it by resetting the required entries in the partition map cache after
receiving a new relation mapping from the publisher.

Reported-by: Shi Yu
Author: Shi Yu, Hou Zhijie
Reviewed-by: Amit Langote, Amit Kapila
Backpatch-through: 13, where it was introduced
Discussion: https://postgr.es/m/OSZPR01MB6310F46CD425A967E4AEF736FDA49@OSZPR01MB6310.jpnprd01.prod.outlook.com
2022-06-16 08:45:07 +05:30
Andres Freund 905c020bef Add missing 'extern' to function prototypes.
Postgres style is to spell out extern. Noticed while scripting adding
PGDLLIMPORT markers to functions.

Discussion: https://postgr.es/m/20220512164513.vaheofqp2q24l65r@alap3.anarazel.de
2022-05-12 12:39:33 -07:00
Tom Lane 23e7b38bfe Pre-beta mechanical code beautification.
Run pgindent, pgperltidy, and reformat-dat-files.
I manually fixed a couple of comments that pgindent uglified.
2022-05-12 15:17:30 -04:00
Amit Kapila f95d53eded Fix the logical replication timeout during large transactions.
The problem is that we don't send keep-alive messages for a long time
while processing large transactions during logical replication where we
don't send any data of such transactions. This can happen when the table
modified in the transaction is not published or because all the changes
got filtered. We do try to send the keep_alive if necessary at the end of
the transaction (via WalSndWriteData()) but by that time the
subscriber-side can timeout and exit.

To fix this we try to send the keepalive message if required after
processing certain threshold of changes.

Reported-by: Fabrice Chapuis
Author: Wang wei and Amit Kapila
Reviewed By: Masahiko Sawada, Euler Taveira, Hou Zhijie, Hayato Kuroda
Backpatch-through: 10
Discussion: https://postgr.es/m/CAA5-nLARN7-3SLU_QUxfy510pmrYK6JJb=bk3hcgemAM_pAv+w@mail.gmail.com
2022-05-11 11:11:44 +05:30
David Rowley a00fd066b1 Add missing spaces after single-line comments
Only 1 of 3 of these changes appear to be handled by pgindent. That change
is new to v15.  The remaining two appear to be left alone by pgindent. The
exact reason for that is not 100% clear to me.  It seems related to the
fact that it's a line that contains *only* a single line comment and no
actual code.  It does not seem worth investigating this in too much
detail.  In any case, these do not conform to our usual practices, so fix
them.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20220411020336.GB26620@telsasoft.com
2022-04-14 09:28:56 +12:00
Michael Paquier a4b57543ac Rename backup_compression.{c,h} to compression.{c,h}
Compression option handling (level, algorithm or even workers) can be
used across several parts of the system and not only base backups.
Structures, objects and routines are renamed in consequence, to remove
the concept of base backups from this part of the code making this
change straight-forward.

pg_receivewal, that has gained support for LZ4 since babbbb5, will make
use of this infrastructure for its set of compression options, bringing
more consistency with pg_basebackup.  This cleanup needs to be done
before releasing a beta of 15.  pg_dump is a potential future target, as
well, and adding more compression options to it may happen in 16~.

Author: Michael Paquier
Reviewed-by: Robert Haas, Georgios Kokolatos
Discussion: https://postgr.es/m/YlPQGNAAa04raObK@paquier.xyz
2022-04-12 13:38:54 +09:00
Robert Haas 8ec569479f Apply PGDLLIMPORT markings broadly.
Up until now, we've had a policy of only marking certain variables
in the PostgreSQL header files with PGDLLIMPORT, but now we've
decided to mark them all. This means that extensions running on
Windows should no longer operate at a disadvantage as compared to
extensions running on Linux: if the variable is present in a header
file, it should be accessible.

Discussion: http://postgr.es/m/CA+TgmoYanc1_FSfimhgiWSqVyP5KKmh5NP2BWNwDhO8Pg2vGYQ@mail.gmail.com
2022-04-08 08:16:38 -04:00
Tomas Vondra 2c7ea57e56 Revert "Logical decoding of sequences"
This reverts a sequence of commits, implementing features related to
logical decoding and replication of sequences:

 - 0da92dc530
 - 80901b3291
 - b779d7d8fd
 - d5ed9da41d
 - a180c2b34d
 - 75b1521dae
 - 2d2232933b
 - 002c9dd97a
 - 05843b1aa4

The implementation has issues, mostly due to combining transactional and
non-transactional behavior of sequences. It's not clear how this could
be fixed, but it'll require reworking significant part of the patch.

Discussion: https://postgr.es/m/95345a19-d508-63d1-860a-f5c2f41e8d40@enterprisedb.com
2022-04-07 20:06:36 +02:00
Andres Freund e41aed674f pgstat: revise replication slot API in preparation for shared memory stats.
Previously the pgstat <-> replication slots API was done with on the basis of
names. However, the upcoming move to storing stats in shared memory makes it
more convenient to use a integer as key.

Change the replication slot functions to take the slot rather than the slot
name, and expose ReplicationSlotIndex() to compute the index of an replication
slot. Special handling will be required for restarts, as the index is not
stable across restarts. For now pgstat internally still uses names.

Rename pgstat_report_replslot_{create,drop}() to
pgstat_{create,drop}_replslot() to match the functions for other kinds of
stats.

Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/20220404041516.cctrvpadhuriawlq@alap3.anarazel.de
2022-04-06 18:38:24 -07:00
Amit Kapila d5a9d86d8f Skip empty transactions for logical replication.
The current logical replication behavior is to send every transaction to
subscriber even if the transaction is empty. This can happen because
transaction doesn't contain changes from the selected publications or all
the changes got filtered. It is a waste of CPU cycles and network
bandwidth to build/transmit these empty transactions.

This patch addresses the above problem by postponing the BEGIN message
until the first change is sent. While processing a COMMIT message, if
there was no other change for that transaction, do not send the COMMIT
message. This allows us to skip sending BEGIN/COMMIT messages for empty
transactions.

When skipping empty transactions in synchronous replication mode, we send
a keepalive message to avoid delaying such transactions.

Author: Ajin Cherian, Hou Zhijie, Euler Taveira
Reviewed-by: Peter Smith, Takamichi Osumi, Shi Yu, Masahiko Sawada, Greg Nancarrow, Vignesh C, Amit Kapila
Discussion: https://postgr.es/m/CAMkU=1yohp9-dv48FLoSPrMqYEyyS5ZWkaZGD41RJr10xiNo_Q@mail.gmail.com
2022-03-30 07:41:05 +05:30
Tomas Vondra 923def9a53 Allow specifying column lists for logical replication
This allows specifying an optional column list when adding a table to
logical replication. The column list may be specified after the table
name, enclosed in parentheses. Columns not included in this list are not
sent to the subscriber, allowing the schema on the subscriber to be a
subset of the publisher schema.

For UPDATE/DELETE publications, the column list needs to cover all
REPLICA IDENTITY columns. For INSERT publications, the column list is
arbitrary and may omit some REPLICA IDENTITY columns. Furthermore, if
the table uses REPLICA IDENTITY FULL, column list is not allowed.

The column list can contain only simple column references. Complex
expressions, function calls etc. are not allowed. This restriction could
be relaxed in the future.

During the initial table synchronization, only columns included in the
column list are copied to the subscriber. If the subscription has
several publications, containing the same table with different column
lists, columns specified in any of the lists will be copied.

This means all columns are replicated if the table has no column list
at all (which is treated as column list with all columns), or when of
the publications is defined as FOR ALL TABLES (possibly IN SCHEMA that
matches the schema of the table).

For partitioned tables, publish_via_partition_root determines whether
the column list for the root or the leaf relation will be used. If the
parameter is 'false' (the default), the list defined for the leaf
relation is used. Otherwise, the column list for the root partition
will be used.

Psql commands \dRp+ and \d <table-name> now display any column lists.

Author: Tomas Vondra, Alvaro Herrera, Rahila Syed
Reviewed-by: Peter Eisentraut, Alvaro Herrera, Vignesh C, Ibrar Ahmed,
Amit Kapila, Hou zj, Peter Smith, Wang wei, Tang, Shi yu
Discussion: https://postgr.es/m/CAH2L28vddB_NFdRVpuyRBJEBWjz4BSyTB=_ektNRH8NJ1jf95g@mail.gmail.com
2022-03-26 01:01:27 +01:00
Tomas Vondra 75b1521dae Add decoding of sequences to built-in replication
This commit adds support for decoding of sequences to the built-in
replication (the infrastructure was added by commit 0da92dc530).

The syntax and behavior mostly mimics handling of tables, i.e. a
publication may be defined as FOR ALL SEQUENCES (replicating all
sequences in a database), FOR ALL SEQUENCES IN SCHEMA (replicating
all sequences in a particular schema) or individual sequences.

To publish sequence modifications, the publication has to include
'sequence' action. The protocol is extended with a new message,
describing sequence increments.

A new system view pg_publication_sequences lists all the sequences
added to a publication, both directly and indirectly. Various psql
commands (\d and \dRp) are improved to also display publications
including a given sequence, or sequences included in a publication.

Author: Tomas Vondra, Cary Huang
Reviewed-by: Peter Eisentraut, Amit Kapila, Hannu Krosing, Andres
             Freund, Petr Jelinek
Discussion: https://postgr.es/m/d045f3c2-6cfb-06d3-5540-e63c320df8bc@enterprisedb.com
Discussion: https://postgr.es/m/1710ed7e13b.cd7177461430746.3372264562543607781@highgo.ca
2022-03-24 18:49:27 +01:00
Robert Haas ffd53659c4 Replace BASE_BACKUP COMPRESSION_LEVEL option with COMPRESSION_DETAIL.
There are more compression parameters that can be specified than just
an integer compression level, so rename the new COMPRESSION_LEVEL
option to COMPRESSION_DETAIL before it gets released. Introduce a
flexible syntax for that option to allow arbitrary options to be
specified without needing to adjust the main replication grammar,
and common code to parse it that is shared between the client and
the server.

This commit doesn't actually add any new compression parameters,
so the only user-visible change is that you can now type something
like pg_basebackup --compress gzip:level=5 instead of writing just
pg_basebackup --compress gzip:5. However, it should make it easy to
add new options. If for example gzip starts offering fries, we can
support pg_basebackup --compress gzip:level=5,fries=true for the
benefit of users who want fries with that.

Along the way, this fixes a few things in pg_basebackup so that the
pg_basebackup can be used with a server-side compression algorithm
that pg_basebackup itself does not understand. For example,
pg_basebackup --compress server-lz4 could still succeed even if
only the server and not the client has LZ4 support, provided that
the other options to pg_basebackup don't require the client to
decompress the archive.

Patch by me. Reviewed by Justin Pryzby and Dagfinn Ilmari Mannsåker.

Discussion: http://postgr.es/m/CA+TgmoYvpetyRAbbg1M8b3-iHsaN4nsgmWPjOENu5-doHuJ7fA@mail.gmail.com
2022-03-23 09:19:14 -04:00
Robert Haas e4ba69f3f4 Allow extensions to add new backup targets.
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
2022-03-15 13:22:04 -04:00
Robert Haas 7cf085f077 Add support for zstd base backup compression.
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
2022-03-08 09:52:43 -05:00
Amit Kapila 52e4f0cd47 Allow specifying row filters for logical replication of tables.
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
2022-02-22 08:11:50 +05:30
Andres Freund 2f6501fa3c Move replication slot release to before_shmem_exit().
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
2022-02-14 17:08:17 -08:00
Robert Haas dab298471f Add suport for server-side LZ4 base backup compression.
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
2022-02-11 08:29:38 -05:00
Tomas Vondra 0da92dc530 Logical decoding of sequences
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
2022-02-10 18:43:51 +01:00
Robert Haas 0d4513b613 Remove server support for the previous base backup protocol.
Commit cc333f3233 added a new COPY
sub-protocol for taking base backups, but retained support for the
previous protocol. For the same reasons articulated in the message
for commit 9cd28c2e5f, remove support
for the previous protocol from the server.

Discussion: http://postgr.es/m/CA+TgmoazKcKUWtqVa0xZqSzbKgTH+X-aw4V7GyLD68EpDLMh8A@mail.gmail.com
2022-02-10 12:12:43 -05:00
Michael Paquier 410aa248e5 Fix various typos, grammar and code style in comments and docs
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
2022-01-25 09:40:04 +09:00
Tom Lane 6aa5186146 Fix limitations on what SQL commands can be issued to a walsender.
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
2022-01-24 15:33:38 -05:00
Robert Haas 0ad8032910 Server-side gzip compression.
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
2022-01-24 15:13:18 -05:00
Robert Haas 3500ccc39b Support base backup targets.
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
2022-01-20 10:46:33 -05:00
Jeff Davis 7a5f6b4748 Make logical decoding a part of the rmgr.
Add a new rmgr method, rm_decode, and use that rather than a switch
statement.

In preparation for rmgr extensibility.

Reviewed-by: Julien Rouhaud
Discussion: https://postgr.es/m/ed1fb2e22d15d3563ae0eb610f7b61bb15999c0a.camel%40j-davis.com
Discussion: https://postgr.es/m/20220118095332.6xtlcjoyxobv6cbk@jrouhaud
2022-01-19 14:58:49 -08:00
Robert Haas cc333f3233 Modify pg_basebackup to use a new COPY subprotocol for base backups.
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
2022-01-18 13:47:49 -05:00