Commit Graph

261 Commits

Author SHA1 Message Date
Tomas Vondra e685ca63ca Remove pg_xact from pg_stat_reset_slru docs
This should have been included in 2e08d314ed.

Reported-by: Fujii Masao
Discussion: https://postgr.es/m/20200119143707.gyinppnigokesjok@development
2020-05-02 15:26:47 +02:00
Michael Paquier 8128b0c152 Fix collection of typos and grammar mistakes in the tree, volume 2
This fixes some comments and documentation new as of Postgres 13, and is
a follow-up of the work done in dd0f37e.

Author: Justin Pryzby
Discussion: https://postgr.es/m/20200408165653.GF2228@telsasoft.com
2020-04-14 14:45:43 +09:00
Thomas Munro 4c04be9b05 Introduce xid8-based functions to replace txid_XXX.
The txid_XXX family of fmgr functions exposes 64 bit transaction IDs to
users as int8.  Now that we have an SQL type xid8 for FullTransactionId,
define a new set of functions including pg_current_xact_id() and
pg_current_snapshot() based on that.  Keep the old functions around too,
for now.

It's a bit sneaky to use the same C functions for both, but since the
binary representation is identical except for the signedness of the
type, and since older functions are the ones using the wrong signedness,
and since we'll presumably drop the older ones after a reasonable period
of time, it seems reasonable to switch to FullTransactionId internally
and share the code for both.

Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Takao Fujii <btfujiitkp@oss.nttdata.com>
Reviewed-by: Yoshikazu Imai <imai.yoshikazu@fujitsu.com>
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/20190725000636.666m5mad25wfbrri%40alap3.anarazel.de
2020-04-07 12:04:32 +12:00
Fujii Masao 18808f8c89 Add wait events for recovery conflicts.
This commit introduces new wait events RecoveryConflictSnapshot and
RecoveryConflictTablespace. The former is reported while waiting for
recovery conflict resolution on a vacuum cleanup. The latter is reported
while waiting for recovery conflict resolution on dropping tablespace.

Also this commit changes the code so that the wait event Lock is reported
while waiting in ResolveRecoveryConflictWithVirtualXIDs() for recovery
conflict resolution on a lock. Basically the wait event Lock is reported
during that wait, but previously was not reported only when that wait
happened in ResolveRecoveryConflictWithVirtualXIDs().

Author: Masahiko Sawada
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CA+fd4k4mXWTwfQLS3RPwGr4xnfAEs1ysFfgYHvmmoUgv6Zxvmg@mail.gmail.com
2020-04-03 12:15:56 +09:00
Tomas Vondra 2c220ca46f Fix typo in SLRU stats documentation
Author: Noriyoshi Shinoda
Discussion: https://www.postgresql.org/message-id/flat/20200119143707.gyinppnigokesjok@development
2020-04-02 14:26:27 +02:00
Tomas Vondra 28cac71bd3 Collect statistics about SLRU caches
There's a number of SLRU caches used to access important data like clog,
commit timestamps, multixact, asynchronous notifications, etc. Until now
we had no easy way to monitor these shared caches, compute hit ratios,
number of reads/writes etc.

This commit extends the statistics collector to track this information
for a predefined list of SLRUs, and also introduces a new system view
pg_stat_slru displaying the data.

The list of built-in SLRUs is fixed, but additional SLRUs may be defined
in extensions. Unfortunately, there's no suitable registry of SLRUs, so
this patch simply defines a fixed list of SLRUs with entries for the
built-in ones and one entry for all additional SLRUs. Extensions adding
their own SLRU are fairly rare, so this seems acceptable.

This patch only allows monitoring of SLRUs, not tuning. The SLRU sizes
are still fixed (hard-coded in the code) and it's not entirely clear
which of the SLRUs might need a GUC to tune size. In a way, allowing us
to determine that is one of the goals of this patch.

Bump catversion as the patch introduces new functions and system view.

Author: Tomas Vondra
Reviewed-by: Alvaro Herrera
Discussion: https://www.postgresql.org/message-id/flat/20200119143707.gyinppnigokesjok@development
2020-04-02 02:34:21 +02:00
David Rowley b07642dbcd Trigger autovacuum based on number of INSERTs
Traditionally autovacuum has only ever invoked a worker based on the
estimated number of dead tuples in a table and for anti-wraparound
purposes. For the latter, with certain classes of tables such as
insert-only tables, anti-wraparound vacuums could be the first vacuum that
the table ever receives. This could often lead to autovacuum workers being
busy for extended periods of time due to having to potentially freeze
every page in the table. This could be particularly bad for very large
tables. New clusters, or recently pg_restored clusters could suffer even
more as many large tables may have the same relfrozenxid, which could
result in large numbers of tables requiring an anti-wraparound vacuum all
at once.

Here we aim to reduce the work required by anti-wraparound and aggressive
vacuums in general, by triggering autovacuum when the table has received
enough INSERTs. This is controlled by adding two new GUCs and reloptions;
autovacuum_vacuum_insert_threshold and
autovacuum_vacuum_insert_scale_factor. These work exactly the same as the
existing scale factor and threshold controls, only base themselves off the
number of inserts since the last vacuum, rather than the number of dead
tuples. New controls were added rather than reusing the existing
controls, to allow these new vacuums to be tuned independently and perhaps
even completely disabled altogether, which can be done by setting
autovacuum_vacuum_insert_threshold to -1.

We make no attempt to skip index cleanup operations on these vacuums as
they may trigger for an insert-mostly table which continually doesn't have
enough dead tuples to trigger an autovacuum for the purpose of removing
those dead tuples. If we were to skip cleaning the indexes in this case,
then it is possible for the index(es) to become bloated over time.

There are additional benefits to triggering autovacuums based on inserts,
as tables which never contain enough dead tuples to trigger an autovacuum
are now more likely to receive a vacuum, which can mark more of the table
as "allvisible" and encourage the query planner to make use of Index Only
Scans.

Currently, we still obey vacuum_freeze_min_age when triggering these new
autovacuums based on INSERTs. For large insert-only tables, it may be
beneficial to lower the table's autovacuum_freeze_min_age so that tuples
are eligible to be frozen sooner. Here we've opted not to zero that for
these types of vacuums, since the table may just be insert-mostly and we
may otherwise freeze tuples that are still destined to be updated or
removed in the near future.

There was some debate to what exactly the new scale factor and threshold
should default to. For now, these are set to 0.2 and 1000, respectively.
There may be some motivation to adjust these before the release.

Author: Laurenz Albe, Darafei Praliaskouski
Reviewed-by: Alvaro Herrera, Masahiko Sawada, Chris Travers, Andres Freund, Justin Pryzby
Discussion: https://postgr.es/m/CAC8Q8t%2Bj36G_bLF%3D%2B0iMo6jGNWnLnWb1tujXuJr-%2Bx8ZCCTqoQ%40mail.gmail.com
2020-03-28 19:20:12 +13:00
Tom Lane ab3e4fbd54 Doc: fix broken markup.
Sloppiness in commit cedffbdb8, noted by Erikjan Rijkers.
(It's fairly unfortunate that xmllint doesn't catch this.)

Discussion: https://postgr.es/m/2e3dc9e4bfa4802d2c9f5fe15bde44de@xs4all.nl
2020-03-24 10:27:09 -04:00
Andres Freund cedffbdb8b Report wait event for cost-based vacuum delay.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20200321040750.GD13662@telsasoft.com
2020-03-23 22:53:22 -07:00
Fujii Masao b8e20d6dab Add wait events for WAL archive and recovery pause.
This commit introduces new wait events BackupWaitWalArchive and
RecoveryPause. The former is reported while waiting for the WAL files
required for the backup to be successfully archived. The latter is
reported while waiting for recovery in pause state to be resumed.

Author: Fujii Masao
Reviewed-by: Michael Paquier, Atsushi Torikoshi, Robert Haas
Discussion: https://postgr.es/m/f0651f8c-9c96-9f29-0ff9-80414a15308a@oss.nttdata.com
2020-03-24 11:12:21 +09:00
Fujii Masao 67e0adfb3f Report NULL as total backup size if it's not estimated.
Previously 0 was reported in pg_stat_progress_basebackup.total_backup
if the total backup size was not estimated. Per discussion, our consensus
is that NULL is better choise as the value in total_backup in that case.
So this commit makes pg_stat_progress_basebackup view report NULL
in total_backup column if the estimation is disabled.

Bump catversion.

Author: Fujii Masao
Reviewed-by: Amit Langote, Magnus Hagander, Alvaro Herrera
Discussion: https://postgr.es/m/CABUevExnhOD89zBDuPvfAAh243RzNpwCPEWNLtMYpKHMB8gbAQ@mail.gmail.com
2020-03-24 10:43:41 +09:00
Fujii Masao fab13dc50b Make pg_basebackup ask the server to estimate the total backup size, by default.
This commit changes pg_basebackup so that it specifies PROGRESS option in
BASE_BACKUP replication command whether --progress is specified or not.
This causes the server to estimate the total backup size and report it in
pg_stat_progress_basebackup.backup_total, by default. This is reasonable
default because the time required for the estimation would not be so large
in most cases.

Also this commit adds new option --no-estimate-size to pg_basebackup.
This option prevents the server from the estimation, and so is useful to
avoid such estimation time if it's too long.

Author: Fujii Masao
Reviewed-by: Magnus Hagander, Amit Langote
Discussion: https://postgr.es/m/CABUevEyDPPSjP7KRvfTXPdqOdY5aWNkqsB5aAXs3bco5ZwtGHg@mail.gmail.com
2020-03-19 17:09:00 +09:00
Fujii Masao 1d253bae57 Rename the recovery-related wait events.
This commit renames RecoveryWalAll and RecoveryWalStream wait events to
RecoveryWalStream and RecoveryRetrieveRetryInterval, respectively,
in order to make the names and what they are more consistent. For example,
previously RecoveryWalAll was reported as a wait event while the recovery
was waiting for WAL from a stream, and which was confusing because the name
was very different from the situation where the wait actually could happen.

The names of macro variables for those wait events also are renamed
accordingly.

This commit also changes the category of RecoveryRetrieveRetryInterval to
Timeout from Activity because the wait event is reported while waiting based
on wal_retrieve_retry_interval.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Atsushi Torikoshi
Discussion: https://postgr.es/m/124997ee-096a-5d09-d8da-2c7a57d0816e@oss.nttdata.com
2020-03-19 15:32:55 +09:00
Fujii Masao dbe0d9892c Correct the descriptions of recovery-related wait events in docs.
This commit corrects the descriptions of RecoveryWalAll and RecoveryWalStream
wait events in the documentation.

Back-patch to v10 where those wait events were added.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Atsushi Torikoshi
Discussion: https://postgr.es/m/124997ee-096a-5d09-d8da-2c7a57d0816e@oss.nttdata.com
2020-03-18 23:07:17 +09:00
Fujii Masao 61b7394045 Fix typo in monitoring.sgml.
Author: Noriyoshi Shinoda
2020-03-03 15:01:47 +09:00
Fujii Masao e65497df8f Report progress of streaming base backup.
This commit adds pg_stat_progress_basebackup view that reports
the progress while an application like pg_basebackup is taking
a base backup. This uses the progress reporting infrastructure
added by c16dc1aca5, adding support for streaming base backup.

Bump catversion.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Amit Langote, Sergei Kornilov
Discussion: https://postgr.es/m/9ed8b801-8215-1f3d-62d7-65bff53f6e94@oss.nttdata.com
2020-03-03 12:03:43 +09:00
Michael Paquier ddfc3c1499 Fix grammar in monitoring.sgml
This is related to progress reporting for ANALYZE and partitioned
tables.

Author: Amit Langote
Reviewed-by: Daniel Gustafsson, Julien Rouhaud
Discussion: https://postgr.es/m/CA+HiwqGx6C=-bFTX=ryMThyvM7CcSC3b1x8_6zh4Uo41Kvu-zw@mail.gmail.com
2020-02-18 10:49:44 +09:00
Fujii Masao f4ae722141 Add description about GSSOpenServer wait event into document.
This commit also updates wait event enum into alphabetical order.
Previously the enum entry for GSSOpenServer was added out-of-order.

Back-patch to v12 where commit b0b39f72b9 introduced
GSSOpenServer wait event. In v12, the commit doesn't include
the update of wait event enum, not to break ABI.

Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/949931aa-4ed4-d867-a7b5-de9c02b2292b@oss.nttdata.com
2020-02-17 16:16:08 +09:00
Fujii Masao e593148d43 Add description about LogicalRewriteTruncate wait event into document.
Back-patch to v10 where commit 249cf070e3 introduced
LogicalRewriteTruncate wait event.

Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/949931aa-4ed4-d867-a7b5-de9c02b2292b@oss.nttdata.com
2020-02-17 15:33:32 +09:00
Tom Lane c185a57753 Revert "docs: change "default role" wording to "predefined role""
This reverts commit 0e936a2148.

Per discussion, we can't change the section title without some
web-site work, so revert this change temporarily.

Discussion: https://postgr.es/m/157742545062.1149.11052653770497832538@wrigleys.postgresql.org
2020-02-09 14:19:46 -05:00
Michael Paquier b025f32e0b Add leader_pid to pg_stat_activity
This new field tracks the PID of the group leader used with parallel
query.  For parallel workers and the leader, the value is set to the
PID of the group leader.  So, for the group leader, the value is the
same as its own PID.  Note that this reflects what PGPROC stores in
shared memory, so as leader_pid is NULL if a backend has never been
involved in parallel query.  If the backend is using parallel query or
has used it at least once, the value is set until the backend exits.

Author: Julien Rouhaud
Reviewed-by: Sergei Kornilov, Guillaume Lelarge, Michael Paquier, Tomas
Vondra
Discussion: https://postgr.es/m/CAOBaU_Yy5bt0vTPZ2_LUM6cUcGeqmYNoJ8-Rgto+c2+w3defYA@mail.gmail.com
2020-02-06 09:18:06 +09:00
Michael Paquier 5ba40b6231 Doc: Fix and tweak documentation for ANALYZE reporting
The docs had some typos and grammar mistakes, and its indentation was
inconsistent.

Author: Amit Langote, Justin Pryzby
Discussion: https://postgr.es/m/20200116151930.GM26045@telsasoft.com
2020-01-23 17:01:46 +09:00
Alvaro Herrera a166d408eb Report progress of ANALYZE commands
This uses the progress reporting infrastructure added by c16dc1aca5,
adding support for ANALYZE.

Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Co-authored-by: Tatsuro Yamada <tatsuro.yamada.tf@nttcom.co.jp>
Reviewed-by: Julien Rouhaud, Robert Haas, Anthony Nowocien, Kyotaro Horiguchi,
	Vignesh C, Amit Langote
2020-01-15 11:14:39 -03:00
Bruce Momjian 0e936a2148 docs: change "default role" wording to "predefined role"
The new wording was determined to be more accurate.  Also, update
release note links that reference these sections.

Reported-by: rirans@comcast.net

Discussion: https://postgr.es/m/157742545062.1149.11052653770497832538@wrigleys.postgresql.org

Backpatch-through: 9.6
2020-01-14 13:13:04 -05:00
Robert Haas 16a4e4aecd Extend the ProcSignal mechanism to support barriers.
A new function EmitProcSignalBarrier() can be used to emit a global
barrier which all backends that participate in the ProcSignal
mechanism must absorb, and a new function WaitForProcSignalBarrier()
can be used to wait until all relevant backends have in fact
absorbed the barrier.

This can be used to coordinate global state changes, such as turning
checksums on while the system is running.

There's no real client of this mechanism yet, although two are
proposed, but an enum has to have at least one element, so this
includes a placeholder type (PROCSIGNAL_BARRIER_PLACEHOLDER) which
should be replaced by the first real client of this mechanism to
get committed.

Andres Freund and Robert Haas, reviewed by Daniel Gustafsson and,
in earlier versions, by Magnus Hagander.

Discussion: http://postgr.es/m/CA+TgmoZwDk=BguVDVa+qdA6SBKef=PKbaKDQALTC_9qoz1mJqg@mail.gmail.com
2019-12-19 14:56:20 -05:00
Amit Kapila 9290ad198b Track statistics for spilling of changes from ReorderBuffer.
This adds the statistics about transactions spilled to disk from
ReorderBuffer.  Users can query the pg_stat_replication view to check
these stats.

Author: Tomas Vondra, with bug-fixes and minor changes by Dilip Kumar
Reviewed-by: Amit Kapila
Discussion: https://postgr.es/m/688b0b7f-2f6c-d827-c27b-216a8e3ea700@2ndquadrant.com
2019-11-21 08:06:51 +05:30
Alvaro Herrera c5e8ea978d pg_stat_activity: document client_port being null
As suggested by Stephen Frost.
Discussion: https://postgr.es/m/20191104160605.GC6962@tamriel.snowman.net
2019-11-12 18:48:41 -03:00
Tom Lane ff43b3e88e Sync our DTrace infrastructure with c.h's definition of type bool.
Since commit d26a810eb, we've defined bool as being either _Bool from
<stdbool.h>, or "unsigned char"; but that commit overlooked the fact
that probes.d has "#define bool char".  For consistency, make it say
"unsigned char" instead.  This should be strictly a cosmetic change,
but it seems best to be in sync.

Formally, in the now-normal case where we're using <stdbool.h>, it'd
be better to write "#define bool _Bool".  However, then we'd need
some build infrastructure to inject that configuration choice into
probes.d, and it doesn't seem worth the trouble.  We only use
<stdbool.h> if sizeof(_Bool) is 1, so having DTrace think that
bool parameters are "unsigned char" should be close enough.

Back-patch to v12 where d26a810eb came in.

Discussion: https://postgr.es/m/CAA4eK1LmaKO7Du9M9Lo=kxGU8sB6aL8fa3sF6z6d5yYYVe3BuQ@mail.gmail.com
2019-11-06 11:11:40 -05:00
Michael Paquier 61ecea45e5 Doc: Add missing step for pg_stat_progress_cluster
There is a step to track when the new heap is written, but this was
missing in the documentation.

Author: Noriyoshi Shinoda
Discussion: https://postgr.es/m/AT5PR8401MB06447FAE88E1592754E958B8EE640@AT5PR8401MB0644.NAMPRD84.PROD.OUTLOOK.COM
Backpatch-through: 12
2019-10-28 14:23:42 +09:00
Peter Eisentraut 8e929a4667 doc: Clean up title case use
Note: Following existing practice, titles of formalpara and step are
not titlecased.
2019-09-08 10:27:29 +02:00
Peter Eisentraut c880096dc1 Add command column to pg_stat_progress_create_index
This allows determining which command is running, similar to
pg_stat_progress_cluster.

Discussion: https://www.postgresql.org/message-id/flat/f0e56b3b-74b7-6cbc-e207-a5ed6bee18dc%402ndquadrant.com
2019-06-04 09:29:02 +02:00
Amit Kapila 9679345f3c Fix typos.
Reported-by: Alexander Lakhin
Author: Alexander Lakhin
Reviewed-by: Amit Kapila and Tom Lane
Discussion: https://postgr.es/m/7208de98-add8-8537-91c0-f8b089e2928c@gmail.com
2019-05-26 18:28:18 +05:30
Magnus Hagander 252b707bc4 Return NULL for checksum failures if checksums are not enabled
Returning 0 could falsely indicate that there is no problem. NULL
correctly indicates that there is no information about potential
problems.

Also return 0 as numbackends instead of NULL for shared objects (as no
connection can be made to a shared object only).

Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
2019-04-17 13:51:48 +02:00
Magnus Hagander 77bd49adba Show shared object statistics in pg_stat_database
This adds a row to the pg_stat_database view with datoid 0 and datname
NULL for those objects that are not in a database. This was added
particularly for checksums, but we were already tracking more satistics
for these objects, just not returning it.

Also add a checksum_last_failure column that holds the timestamptz of
the last checksum failure that occurred in a database (or in a
non-dataabase file), if any.

Author: Julien Rouhaud <rjuju123@gmail.com>
2019-04-12 14:04:50 +02:00
Peter Eisentraut 122fa9f942 doc: Fix whitespace
Author: Julien Rouhaud <rjuju123@gmail.com>
2019-04-08 22:32:46 +02:00
Peter Eisentraut 03f9e5cba0 Report progress of REINDEX operations
This uses the same infrastructure that the CREATE INDEX progress
reporting uses.  Add a column to pg_stat_progress_create_index to
report the OID of the index being worked on.  This was not necessary
for CREATE INDEX, but it's useful for REINDEX.

Also edit the phase descriptions a bit to be more consistent with the
source code comments.

Discussion: https://www.postgresql.org/message-id/ef6a6757-c36a-9e81-123f-13b19e36b7d7%402ndquadrant.com
2019-04-07 12:35:29 +02:00
Peter Eisentraut 106f2eb664 Cast pg_stat_progress_cluster.cluster_index_relid to oid
It's tracked internally as bigint, but when presented to the user it
should be oid.
2019-04-07 10:31:32 +02:00
Stephen Frost b0b39f72b9 GSSAPI encryption support
On both the frontend and backend, prepare for GSSAPI encryption
support by moving common code for error handling into a separate file.
Fix a TODO for handling multiple status messages in the process.
Eliminate the OIDs, which have not been needed for some time.

Add frontend and backend encryption support functions.  Keep the
context initiation for authentication-only separate on both the
frontend and backend in order to avoid concerns about changing the
requested flags to include encryption support.

In postmaster, pull GSSAPI authorization checking into a shared
function.  Also share the initiator name between the encryption and
non-encryption codepaths.

For HBA, add "hostgssenc" and "hostnogssenc" entries that behave
similarly to their SSL counterparts.  "hostgssenc" requires either
"gss", "trust", or "reject" for its authentication.

Similarly, add a "gssencmode" parameter to libpq.  Supported values are
"disable", "require", and "prefer".  Notably, negotiation will only be
attempted if credentials can be acquired.  Move credential acquisition
into its own function to support this behavior.

Add a simple pg_stat_gssapi view similar to pg_stat_ssl, for monitoring
if GSSAPI authentication was used, what principal was used, and if
encryption is being used on the connection.

Finally, add documentation for everything new, and update existing
documentation on connection security.

Thanks to Michael Paquier for the Windows fixes.

Author: Robbie Harwood, with changes to the read/write functions by me.
Reviewed in various forms and at different times by: Michael Paquier,
   Andres Freund, David Steele.
Discussion: https://www.postgresql.org/message-id/flat/jlg1tgq1ktm.fsf@thriss.redhat.com
2019-04-03 15:02:33 -04:00
Alvaro Herrera ab0dfc961b Report progress of CREATE INDEX operations
This uses the progress reporting infrastructure added by c16dc1aca5,
adding support for CREATE INDEX and CREATE INDEX CONCURRENTLY.

There are two pieces to this: one is index-AM-agnostic, and the other is
AM-specific.  The latter is fairly elaborate for btrees, including
reportage for parallel index builds and the separate phases that btree
index creation uses; other index AMs, which are much simpler in their
building procedures, have simplistic reporting only, but that seems
sufficient, at least for non-concurrent builds.

The index-AM-agnostic part is fairly complete, providing insight into
the CONCURRENTLY wait phases as well as block-based progress during the
index validation table scan.  (The index validation index scan requires
patching each AM, which has not been included here.)

Reviewers: Rahila Syed, Pavan Deolasee, Tatsuro Yamada
Discussion: https://postgr.es/m/20181220220022.mg63bhk26zdpvmcj@alvherre.pgsql
2019-04-02 15:18:08 -03:00
Robert Haas 6f97457e0d Add progress reporting for CLUSTER and VACUUM FULL.
This uses the same progress reporting infrastructure added in commit
c16dc1aca5 and extends it to these
additional cases.  We lack the ability to track the internal progress
of sorts and index builds so the information reported is
coarse-grained for some parts of the operation, but it still seems
like a significant improvement over having nothing at all.

Tatsuro Yamada, reviewed by Thomas Munro, Masahiko Sawada, Michael
Paquier, Jeff Janes, Alvaro Herrera, Rafia Sabih, and by me.  A fair
amount of polishing also by me.

Discussion: http://postgr.es/m/59A77072.3090401@lab.ntt.co.jp
2019-03-25 10:59:04 -04:00
Thomas Munro bb16aba50c Enable parallel query with SERIALIZABLE isolation.
Previously, the SERIALIZABLE isolation level prevented parallel query
from being used.  Allow the two features to be used together by
sharing the leader's SERIALIZABLEXACT with parallel workers.

An extra per-SERIALIZABLEXACT LWLock is introduced to make it safe to
share, and new logic is introduced to coordinate the early release
of the SERIALIZABLEXACT required for the SXACT_FLAG_RO_SAFE
optimization, as follows:

The first backend to observe the SXACT_FLAG_RO_SAFE flag (set by
some other transaction) will 'partially release' the SERIALIZABLEXACT,
meaning that the conflicts and locks it holds are released, but the
SERIALIZABLEXACT itself will remain active because other backends
might still have a pointer to it.

Whenever any backend notices the SXACT_FLAG_RO_SAFE flag, it clears
its own MySerializableXact variable and frees local resources so that
it can skip SSI checks for the rest of the transaction.  In the
special case of the leader process, it transfers the SERIALIZABLEXACT
to a new variable SavedSerializableXact, so that it can be completely
released at the end of the transaction after all workers have exited.

Remove the serializable_okay flag added to CreateParallelContext() by
commit 9da0cc35, because it's now redundant.

Author: Thomas Munro
Reviewed-by: Haribabu Kommi, Robert Haas, Masahiko Sawada, Kevin Grittner
Discussion: https://postgr.es/m/CAEepm=0gXGYhtrVDWOTHS8SQQy_=S9xo+8oCxGLWZAOoeJ=yzQ@mail.gmail.com
2019-03-15 17:47:04 +13:00
Thomas Munro c6c9474aaf Use condition variables to wait for checkpoints.
Previously we used a polling/sleeping loop to wait for checkpoints
to begin and end, which leads to up to a couple hundred milliseconds
of needless thumb-twiddling.  Use condition variables instead.

Author: Thomas Munro
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/CA%2BhUKGLY7sDe%2Bbg1K%3DbnEzOofGoo4bJHYh9%2BcDCXJepb6DQmLw%40mail.gmail.com
2019-03-14 10:59:33 +13:00
Magnus Hagander 6b9e875f72 Track block level checksum failures in pg_stat_database
This adds a column that counts how many checksum failures have occurred
on files belonging to a specific database. Both checksum failures
during normal backend processing and those created when a base backup
detects a checksum failure are counted.

Author: Magnus Hagander
Reviewed by: Julien Rouhaud
2019-03-09 10:47:30 -08:00
Peter Eisentraut 213eae9b8a doc: Add security information about pg_stat_activity
Add a basic note that some columns in pg_stat_activity and related
views are not visible to all users.

Discussion: https://www.postgresql.org/message-id/3018acd9-e5d8-1e85-5ed7-47276cd77569%402ndquadrant.com
2019-02-21 19:49:27 +01:00
Noah Misch 301de4f7d9 Fix CLogTruncationLock documentation.
Back-patch to v10, which introduced the lock.
2019-02-17 00:51:11 -08:00
Peter Eisentraut f60a0e9677 Add more columns to pg_stat_ssl
Add columns client_serial and issuer_dn to pg_stat_ssl.  These allow
uniquely identifying the client certificate.

Rename the existing column clientdn to client_dn, to make the naming
more consistent and easier to read.

Discussion: https://www.postgresql.org/message-id/flat/398754d8-6bb5-c5cf-e7b8-22e5f0983caf@2ndquadrant.com/
2019-02-01 00:33:47 +01:00
Michael Paquier 1707a0d2aa Remove configure switch --disable-strong-random
This removes a portion of infrastructure introduced by fe0a0b5 to allow
compilation of Postgres in environments where no strong random source is
available, meaning that there is no linking to OpenSSL and no
/dev/urandom (Windows having its own CryptoAPI).  No systems shipped
this century lack /dev/urandom, and the buildfarm is actually not
testing this switch at all, so just remove it.  This simplifies
particularly some backend code which included a fallback implementation
using shared memory, and removes a set of alternate regression output
files from pgcrypto.

Author: Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/20181230063219.GG608@paquier.xyz
2019-01-01 20:05:51 +09:00
Michael Paquier 7fee252f6f Add timestamp of last received message from standby to pg_stat_replication
The timestamp generated by the standby at message transmission has been
included in the protocol since its introduction for both the status
update message and hot standby feedback message, but it has never
appeared in pg_stat_replication.  Seeing this timestamp does not matter
much with a cluster which has a lot of activity, but on a mostly-idle
cluster, this makes monitoring able to react faster than the configured
timeouts.

Author: MyungKyu LIM
Reviewed-by: Michael Paquier, Masahiko Sawada
Discussion: https://postgr.es/m/1657809367.407321.1533027417725.JavaMail.jboss@ep2ml404
2018-12-09 16:35:06 +09:00
Michael Paquier 99f9ccee51 Fix invalid value of synchronous_commit in description of flush_lag
"remote_flush" has never been a valid user-facing value, but "on" is.

Author: Maksim Milyutin
Discussion: https://postgr.es/m/27b3b80c-3615-2d76-02c5-44566b53136c@gmail.com
2018-12-05 10:02:47 +09:00
Amit Kapila 621a8ac5af Fix the omission in docs.
Commit 5373bc2a08 has added type for background workers but forgot to
update at one place in the documentation.

Reported-by: John Naylor
Author: John Naylor
Reviewed-by: Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/CAJVSVGVmvgJ8Lq4WBxC3zV5wf0txdCqRSgkWVP+jaBF=HgWscA@mail.gmail.com
2018-11-15 10:56:49 +05:30