Commit Graph

23819 Commits

Author SHA1 Message Date
Amit Kapila 3e577ff602 Optimize the origin drop functionality.
To interlock against concurrent drops, we use to hold ExclusiveLock on
pg_replication_origin till xact commit. This blocks even concurrent drops
of different origins by tablesync workers. So, instead, lock the specific
origin to interlock against concurrent drops.

This reduces the test time variability in src/test/subscription where
multiple tables are being synced.

Author: Vignesh C
Reviewed-by: Hou Zhijie, Amit Kapila
Discussion: https://postgr.es/m/1412708.1674417574@sss.pgh.pa.us
2023-02-03 08:29:08 +05:30
David Rowley 8ca6d49f63 Add helper functions to simplify heapgettup code
Here we add heapgettup_start_page() and heapgettup_continue_page() to
simplify the code in the heapgettup() function.

Author: Melanie Plageman
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/CAAKRu_bvkhka0CZQun28KTqhuUh5ZqY=_T8QEqZqOL02rpi2bw@mail.gmail.com
2023-02-03 12:38:42 +13:00
David Rowley f9bc34fcb6 Further refactor of heapgettup and heapgettup_pagemode
Backward and forward scans share much of the same page acquisition code.
Here we consolidate that code to reduce some duplication.

Additionally, add a new rs_coffset field to HeapScanDescData to track the
offset of the current tuple.  The new field fits nicely into the padding
between a bool and BlockNumber field and saves having to look at the last
returned tuple to figure out which offset we should be looking at for the
current tuple.

Author: Melanie Plageman
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/CAAKRu_bvkhka0CZQun28KTqhuUh5ZqY=_T8QEqZqOL02rpi2bw@mail.gmail.com
2023-02-03 11:48:39 +13:00
Thomas Munro cdf6518ef0 Retire PG_SETMASK() macro.
In the 90s we needed to deal with computers that still had the
pre-standard signal masking APIs.  That hasn't been relevant for a very
long time on Unix systems, and c94ae9d8 got rid of a remaining
dependency in our Windows porting code.  PG_SETMASK didn't expose
save/restore functionality, so we'd already started using sigprocmask()
directly in places, creating the visual distraction of having two ways
to spell it.  It's not part of the API that extensions are expected to
be using (but if they are, the change will be trivial).  It seems like a
good time to drop the old macro and just call the standard POSIX
function.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BKfQgrhHP2DLTohX1WwubaCBHmTzGnAEDPZ-Gug-Xskg%40mail.gmail.com
2023-02-03 11:29:46 +13:00
Dean Rasheed 0736fc1ceb Clarify the choice of rscale in numeric_sqrt().
Improve the comment explaining the choice of rscale in numeric_sqrt(),
and ensure that the code works consistently when other values of
NBASE/DEC_DIGITS are used.

Note that, in practice, we always expect DEC_DIGITS == 4, and this
does not change the computation in that case.

Joel Jacobson and Dean Rasheed

Discussion: https://postgr.es/m/06712c29-98e9-43b3-98da-f234d81c6e49%40app.fastmail.com
2023-02-02 09:41:22 +00:00
Dean Rasheed 9a84f2947b Ensure that numeric.c compiles with other NBASE values.
As noted in the comments, support for different NBASE values is really
only of historical interest, but as long as we're keeping it, we might
as well make sure that it compiles.

Joel Jacobson

Discussion: https://postgr.es/m/06712c29-98e9-43b3-98da-f234d81c6e49%40app.fastmail.com
2023-02-02 09:39:08 +00:00
Amit Kapila 9f2213a7c5 Allow the logical_replication_mode to be used on the subscriber.
Extend the existing developer option 'logical_replication_mode' to help
test the parallel apply of large transactions on the subscriber.

When set to 'buffered', the leader sends changes to parallel apply workers
via a shared memory queue. When set to 'immediate', the leader serializes
all changes to files and notifies the parallel apply workers to read and
apply them at the end of the transaction.

This helps in adding tests to cover the serialization code path in
parallel streaming mode.

Author: Hou Zhijie
Reviewed-by: Peter Smith, Kuroda Hayato, Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/CAA4eK1+wyN6zpaHUkCLorEWNx75MG0xhMwcFhvjqm2KURZEAGw@mail.gmail.com
2023-02-02 08:15:18 +05:30
David Rowley fb1a59de0c Refactor heapam.c adding heapgettup_initial_block function
Here we adjust heapgettup() and heapgettup_pagemode() to move the code
that fetches the first block number to scan out into a helper function.
This removes some code duplication.

Author: Melanie Plageman
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/CAAKRu_bvkhka0CZQun28KTqhuUh5ZqY=_T8QEqZqOL02rpi2bw@mail.gmail.com
2023-02-02 14:17:15 +13:00
Michael Paquier 38cc085464 Simplify main waiting loop of the archiver process
As coded, the timeout given to WaitLatch() was always equal to
PGARCH_AUTOWAKE_INTERVAL, as time() was called two times repeatedly.
This simplification could have been done in d75288f.

While on it, this adjusts a comment in pgarch.c to describe the archiver
in a more neutral way.

Author: Sravan Kumar, Nathan Bossart
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CA+=NbjjqYE9-Lnw7H7DAiS5jebmoMikwZQb_sBP7kgBCn9q6Hg@mail.gmail.com
2023-02-01 15:46:04 +09:00
David Rowley e9aaf06328 Remove dead NoMovementScanDirection code
Here remove some dead code from heapgettup() and heapgettup_pagemode()
which was trying to support NoMovementScanDirection scans.  This code can
never be reached as standard_ExecutorRun() never calls ExecutePlan with
NoMovementScanDirection.

Additionally, plans which were scanning an unordered index would use
NoMovementScanDirection rather than ForwardScanDirection.  There was no
real need for this, so here we adjust this so we use ForwardScanDirection
for unordered index scans.  A comment in pathnodes.h claimed that
NoMovementScanDirection was used for PathKey reasons, but if that was
true, it no longer is, per code in build_index_paths().

This does change the non-text format of the EXPLAIN output so that
unordered index scans now have a "Forward" scan direction rather than
"NoMovement".  The text format of EXPLAIN has not changed.

Author: Melanie Plageman
Reviewed-by: Tom Lane, David Rowley
Discussion: https://postgr.es/m/CAAKRu_bvkhka0CZQun28KTqhuUh5ZqY=_T8QEqZqOL02rpi2bw@mail.gmail.com
2023-02-01 10:52:41 +13:00
Tom Lane eae0e20def Remove over-optimistic Assert.
In commit 2489d76c4, I'd thought it'd be safe to assert that a
PlaceHolderVar appearing in a scan-level expression has empty
nullingrels.  However this is not so, as when we determine that a
join relation is certainly empty we'll put its targetlist into a
Result-with-constant-false-qual node, and nothing is done to adjust
the nullingrels of the Vars or PHVs therein.  (Arguably, a Result
used in this way isn't really a scan-level node, but it certainly
isn't an upper node either ...)

It's not clear this is worth any close analysis, so let's just
take out the faulty Assert.

Per report from Robins Tharakan.  I added a test case based on
his example, just in case somebody tries to tighten this up.

Discussion: https://postgr.es/m/CAEP4nAz7Enq3+DEthGG7j27DpuwSRZnW0Nh6jtNh75yErQ_nbA@mail.gmail.com
2023-01-31 11:57:47 -05:00
Michael Paquier 3db72ebcbe Generate code for query jumbling through gen_node_support.pl
This commit changes the query jumbling code in queryjumblefuncs.c to be
generated automatically based on the information of the nodes in the
headers of src/include/nodes/ by using gen_node_support.pl.  This
approach offers many advantages:
- Support for query jumbling for all the utility statements, based on the
state of their parsed Nodes and not only their query string.  This will
greatly ease the switch to normalize the information of some DDLs, like
SET or CALL for example (this is left unchanged and should be part of a
separate discussion).  With this feature, the number of entries stored
for utilities in pg_stat_statements is reduced (for example now
"CHECKPOINT" and "checkpoint" mean the same thing with the same query
ID).
- Documentation of query jumbling directly in the structure definition
of the nodes.  Since this code has been introduced in pg_stat_statements
and then moved to code, the reasons behind the choices of what should be
included in the jumble are rather sparse.  Note that some explanation is
added for the most relevant parts, as a start.
- Overall code reduction and more consistency with the other parts
generating read, write and copy depending on the nodes.

The query jumbling is controlled by a couple of new node attributes,
documented in nodes/nodes.h:
- custom_query_jumble, to mark a Node as having a custom
implementation.
- no_query_jumble, to ignore entirely a Node.
- query_jumble_ignore, to ignore a field in a Node.
- query_jumble_location, to mark a location in a Node, for
normalization.  This can apply only to int fields, with "location" in
their name (only Const as of this commit).

There should be no compatibility impact on pg_stat_statements, as the
new code applies the jumbling to the same fields for each node (its
regression tests have no modification, for one).

Some benchmark of the query jumbling between HEAD and this commit for
SELECT and DMLs has proved that this new code does not cause a
performance regression, with computation times close for both methods.
For utility queries, the new method is slower than the previous method
of calculating a hash of the query string, though we are talking about
extra ns-level changes based on what I measured, which is unnoticeable
even for OLTP workloads as a query ID is calculated once per query
post-parse analysis.

Author: Michael Paquier
Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
2023-01-31 15:24:05 +09:00
Tom Lane 3bef56e116 Invent "join domains" to replace the below_outer_join hack.
EquivalenceClasses are now understood as applying within a "join
domain", which is a set of inner-joined relations (possibly underneath
an outer join).  We no longer need to treat an EC from below an outer
join as a second-class citizen.

I have hopes of eventually being able to treat outer-join clauses via
EquivalenceClasses, by means of only applying deductions within the
EC's join domain.  There are still problems in the way of that, though,
so for now the reconsider_outer_join_clause logic is still here.

I haven't been able to get rid of RestrictInfo.is_pushed_down either,
but I wonder if that could be recast using JoinDomains.

I had to hack one test case in postgres_fdw.sql to make it still test
what it was meant to, because postgres_fdw is inconsistent about
how it deals with quals containing non-shippable expressions; see
https://postgr.es/m/1691374.1671659838@sss.pgh.pa.us.  That should
be improved, but I don't think it's within the scope of this patch
series.

Patch by me; thanks to Richard Guo for review.

Discussion: https://postgr.es/m/830269.1656693747@sss.pgh.pa.us
2023-01-30 13:50:25 -05:00
Tom Lane b448f1c8d8 Do assorted mop-up in the planner.
Remove RestrictInfo.nullable_relids, along with a good deal of
infrastructure that calculated it.  One use-case for it was in
join_clause_is_movable_to, but we can now replace that usage with
a check to see if the clause's relids include any outer join
that can null the target relation.  The other use-case was in
join_clause_is_movable_into, but that test can just be dropped
entirely now that the clause's relids include outer joins.
Furthermore, join_clause_is_movable_into should now be
accurate enough that it will accept anything returned by
generate_join_implied_equalities, so we can restore the Assert
that was diked out in commit 95f4e59c3.

Remove the outerjoin_delayed mechanism.  We needed this before to
prevent quals from getting evaluated below outer joins that should
null some of their vars.  Now that we consider varnullingrels while
placing quals, that's taken care of automatically, so throw the
whole thing away.

Teach remove_useless_result_rtes to also remove useless FromExprs.
Having done that, the delay_upper_joins flag serves no purpose any
more and we can remove it, largely reverting 11086f2f2.

Use constant TRUE for "dummy" clauses when throwing back outer joins.
This improves on a hack I introduced in commit 6a6522529.  If we
have a left-join clause l.x = r.y, and a WHERE clause l.x = constant,
we generate r.y = constant and then don't really have a need for the
join clause.  But we must throw the join clause back anyway after
marking it redundant, so that the join search heuristics won't think
this is a clauseless join and avoid it.  That was a kluge introduced
under time pressure, and after looking at it I thought of a better
way: let's just introduce constant-TRUE "join clauses" instead,
and get rid of them at the end.  This improves the generated plans for
such cases by not having to test a redundant join clause.  We can also
get rid of the ugly hack used to mark such clauses as redundant for
selectivity estimation.

Patch by me; thanks to Richard Guo for review.

Discussion: https://postgr.es/m/830269.1656693747@sss.pgh.pa.us
2023-01-30 13:44:36 -05:00
Tom Lane 2489d76c49 Make Vars be outer-join-aware.
Traditionally we used the same Var struct to represent the value
of a table column everywhere in parse and plan trees.  This choice
predates our support for SQL outer joins, and it's really a pretty
bad idea with outer joins, because the Var's value can depend on
where it is in the tree: it might go to NULL above an outer join.
So expression nodes that are equal() per equalfuncs.c might not
represent the same value, which is a huge correctness hazard for
the planner.

To improve this, decorate Var nodes with a bitmapset showing
which outer joins (identified by RTE indexes) may have nulled
them at the point in the parse tree where the Var appears.
This allows us to trust that equal() Vars represent the same value.
A certain amount of klugery is still needed to cope with cases
where we re-order two outer joins, but it's possible to make it
work without sacrificing that core principle.  PlaceHolderVars
receive similar decoration for the same reason.

In the planner, we include these outer join bitmapsets into the relids
that an expression is considered to depend on, and in consequence also
add outer-join relids to the relids of join RelOptInfos.  This allows
us to correctly perceive whether an expression can be calculated above
or below a particular outer join.

This change affects FDWs that want to plan foreign joins.  They *must*
follow suit when labeling foreign joins in order to match with the
core planner, but for many purposes (if postgres_fdw is any guide)
they'd prefer to consider only base relations within the join.
To support both requirements, redefine ForeignScan.fs_relids as
base+OJ relids, and add a new field fs_base_relids that's set up by
the core planner.

Large though it is, this commit just does the minimum necessary to
install the new mechanisms and get check-world passing again.
Follow-up patches will perform some cleanup.  (The README additions
and comments mention some stuff that will appear in the follow-up.)

Patch by me; thanks to Richard Guo for review.

Discussion: https://postgr.es/m/830269.1656693747@sss.pgh.pa.us
2023-01-30 13:16:20 -05:00
Dean Rasheed fe9e658f4d Ensure that MERGE recomputes GENERATED expressions properly.
This fixes a bug that, under some circumstances, would cause MERGE to
fail to properly recompute expressions for GENERATED STORED columns.

Formerly, ExecInitModifyTable() did not call ExecInitStoredGenerated()
for a MERGE command, which meant that the generated expressions
information was not computed until later, when the first merge action
was executed. However, if the first merge action to execute was an
UPDATE, then ExecInitStoredGenerated() could decide to skip some some
generated columns, if the columns on which they depended were not
updated, which was a problem if the MERGE also contained an INSERT
action, for which no generated columns should be skipped.

So fix by having ExecInitModifyTable() call ExecInitStoredGenerated()
for MERGE, and assume that it isn't safe to skip any generated columns
in a MERGE. Possibly that could be relaxed, by allowing some generated
columns to be skipped for a MERGE without an INSERT action, but it's
not clear that it's worth the effort.

Noticed while investigating bug #17759. Back-patch to v15, where MERGE
was added.

Dean Rasheed, reviewed by Tom Lane.

Discussion:
  https://postgr.es/m/17759-e76d9bece1b5421c%40postgresql.org
  https://postgr.es/m/CAEZATCXb_ezoMCcL0tzKwRGA1x0oeE%3DawTaysRfTPq%2B3wNJn8g%40mail.gmail.com
2023-01-30 10:04:57 +00:00
Amit Kapila 1e8b61735c Rename GUC logical_decoding_mode to logical_replication_mode.
Rename the developer option 'logical_decoding_mode' to the more flexible
name 'logical_replication_mode' because doing so will make it easier to
extend this option in the future to help test other areas of logical
replication.

Currently, it is used on the publisher side to allow streaming or
serializing each change in logical decoding. In the upcoming patch, we are
planning to use it on the subscriber. On the subscriber, it will allow
serializing the changes to file and notifies the parallel apply workers to
read and apply them at the end of the transaction.

We discussed exposing this parameter as a subscription option but
it did not seem advisable since it is primarily used for testing/debugging
and there is no other such parameter. We also discussed having separate
GUCs for publisher and subscriber but for current testing/debugging
requirements, one GUC is sufficient.

Author: Hou Zhijie
Reviewed-by: Peter Smith, Kuroda Hayato, Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/CAD21AoAy2c=Mx=FTCs+EwUsf2kQL5MmU3N18X84k0EmCXntK4g@mail.gmail.com
Discussion: https://postgr.es/m/CAA4eK1+wyN6zpaHUkCLorEWNx75MG0xhMwcFhvjqm2KURZEAGw@mail.gmail.com
2023-01-30 08:02:08 +05:30
Thomas Munro 8d2c1913ed Remove unneeded volatile qualifiers from postmaster.c.
Several flags were marked volatile and in some cases used sig_atomic_t
because they were accessed from signal handlers.  After commit 7389aad6,
we can just use unqualified bool.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA%2BhUKGLMoeZNZY6gYdLUQmuoW_a8bKyLvtuZkd_zHcGVOfDzBA%40mail.gmail.com
2023-01-28 15:06:23 +13:00
Tom Lane e4e89eb5bb Minor GUC code refactoring.
Split out "ConfigOptionIsVisible" to perform the privilege
check for GUC_SUPERUSER_ONLY GUCs (which these days can also
be read by pg_read_all_settings role members), and move the
should-we-show-it checks from GetConfigOptionValues to its
sole caller.

This commit also removes get_explain_guc_options's check of
GUC_NO_SHOW_ALL, which seems to have got cargo-culted in there.
While there's no obvious use-case for marking a GUC both
GUC_EXPLAIN and GUC_NO_SHOW_ALL, if it were set up that way
one would expect EXPLAIN to show it --- if that's not what
you want, then don't set GUC_EXPLAIN.

In passing, simplify the loop logic in show_all_settings.

Nitin Jadhav, Bharath Rupireddy, Tom Lane

Discussion: https://postgr.es/m/CAMm1aWYgfekpRK-Jz5=pM_bV+Om=ktGq1vxTZ_dr1Z6MV-qokA@mail.gmail.com
2023-01-27 12:13:41 -05:00
David Rowley 456fa635a9 Teach planner about more monotonic window functions
9d9c02ccd introduced runConditions for window functions to allow
monotonic window function evaluation to be made more efficient when the
window function value went beyond some value that it would never go back
from due to its monotonic nature.  That commit added prosupport functions
to inform the planner that row_number(), rank(), dense_rank() and some
forms of count(*) were monotonic.  Here we add support for ntile(),
cume_dist() and percent_rank().

Reviewed-by: Melanie Plageman
Discussion: https://postgr.es/m/CAApHDvqR+VqB8s+xR-24bzJbU8xyFrBszJ17qKgECf7cWxLCaA@mail.gmail.com
2023-01-27 16:08:41 +13:00
Tom Lane 3a28d78089 Improve TimestampDifferenceMilliseconds to cope with overflow sanely.
We'd like to use TimestampDifferenceMilliseconds with the stop_time
possibly being TIMESTAMP_INFINITY, but up to now it's disclaimed
responsibility for overflow cases.  Define it to clamp its output to
the range [0, INT_MAX], handling overflow correctly.  (INT_MAX rather
than LONG_MAX seems appropriate, because the function is already
described as being intended for calculating wait times for WaitLatch
et al, and that infrastructure only handles waits up to INT_MAX.
Also, this choice gets rid of cross-platform behavioral differences.)

Having done that, we can replace some ad-hoc code in walreceiver.c
with a simple call to TimestampDifferenceMilliseconds.

While at it, fix some buglets in existing callers of
TimestampDifferenceMilliseconds: basebackup_copy.c had not read the
memo about TimestampDifferenceMilliseconds never returning a negative
value, and postmaster.c had not read the memo about Min() and Max()
being macros with multiple-evaluation hazards.  Neither of these
quite seem worth back-patching.

Patch by me; thanks to Nathan Bossart for review.

Discussion: https://postgr.es/m/3126727.1674759248@sss.pgh.pa.us
2023-01-26 17:09:12 -05:00
Tom Lane 24ff700f6a Code review for commit 05a7be935.
Avoid having walreceiver code know explicitly about the precision
and underlying datatype of TimestampTz.  (There is still one
calculation that knows that, which should be replaced with use of
TimestampDifferenceMilliseconds; but we need to figure out what to do
about overflow cases first.)

In support of this, provide a TimestampTzPlusSeconds macro, as well
as TIMESTAMP_INFINITY and TIMESTAMP_MINUS_INFINITY macros.  (We could
have used the existing DT_NOEND and DT_NOBEGIN symbols, but I judged
those too opaque and confusing.)

Move GetCurrentTimestamp calls so that it's more obvious that we
are not using stale values of "now" anyplace.  This doesn't result
in net more calls, and might indeed make for net fewer.

Avoid having a dummy value in the WalRcvWakeupReason enum, so that
we can hope for the compiler to catch overlooked switch cases.

Nathan Bossart and Tom Lane

Discussion: https://postgr.es/m/20230125235004.GA1327755@nathanxps13
2023-01-26 12:51:00 -05:00
Peter Eisentraut 37e2673350 Don't install postmaster symlink anymore
This has long been deprecated.  Some of the build systems didn't even
install it.

Also remove man page.

Reviewed-by: Karl O. Pinc <kop@karlpinc.com>
Discussion: https://www.postgresql.org/message-id/flat/ece84b69-8f94-8b88-925f-64207cb3a2f0@enterprisedb.com
2023-01-26 11:33:01 +01:00
Peter Geoghegan 6c6b497266 Revert "Add eager and lazy freezing strategies to VACUUM."
This reverts commit 4d41799261.  Broad
concerns about regressions caused by eager freezing strategy have been
raised.  Whether or not these concerns can be worked through in any time
frame is far from certain.

Discussion: https://postgr.es/m/20230126004347.gepcmyenk2csxrri@awork3.anarazel.de
2023-01-25 22:22:27 -08:00
Michael Paquier 9d2d9728b8 Make auto_explain print the query identifier in verbose mode
When auto_explain.log_verbose is on, auto_explain should print in the
logs plans equivalent to the EXPLAIN (VERBOSE).  However, when
compute_query_id is on, query identifiers were not showing up, being
only handled by EXPLAIN (VERBOSE).  This brings auto_explain on par with
EXPLAIN regarding that.  Note that like EXPLAIN, auto_explain does not
show the query identifier when compute_query_id=regress.

The change is done so as the choice of printing the query identifier is
done in ExplainPrintPlan() rather than in ExplainOnePlan(), to avoid a
duplication of the logic dealing with the query ID.  auto_explain is the
only in-core caller of ExplainPrintPlan().

While looking at the area, I have noticed that more consolidation
between EXPLAIN and auto_explain would be in order for the logging of
the plan duration and the buffer usage.  This refactoring is left as a
future change.

Author: Atsushi Torikoshi
Reviewed-by: Justin Pryzby, Julien Rouhaud
Discussion: https://postgr.es/m/1ea21936981f161bccfce05765c03bee@oss.nttdata.com
2023-01-26 12:23:16 +09:00
Thomas Munro ffcf6f4cfc Fix rare sharedtuplestore.c corruption.
If the final chunk of an oversized tuple being written out to disk was
exactly 32760 bytes, it would be corrupted due to a fencepost bug.

Bug #17619.  Back-patch to 11 where the code arrived.

While testing that (see test module in archives), I (tmunro) noticed
that the per-participant page counter was not initialized to zero as it
should have been; that wasn't a live bug when it was written since DSM
memory was originally always zeroed, but since 14
min_dynamic_shared_memory might be configured and it supplies non-zeroed
memory, so that is also fixed here.

Author: Dmitry Astapov <dastapov@gmail.com>
Discussion: https://postgr.es/m/17619-0de62ceda812b8b5%40postgresql.org
2023-01-26 14:52:19 +13:00
Peter Geoghegan 4d41799261 Add eager and lazy freezing strategies to VACUUM.
Eager freezing strategy avoids large build-ups of all-visible pages.  It
makes VACUUM trigger page-level freezing whenever doing so will enable
the page to become all-frozen in the visibility map.  This is useful for
tables that experience continual growth, particularly strict append-only
tables such as pgbench's history table.  Eager freezing significantly
improves performance stability by spreading out the cost of freezing
over time, rather than doing most freezing during aggressive VACUUMs.
It complements the insert autovacuum mechanism added by commit b07642db.

VACUUM determines its freezing strategy based on the value of the new
vacuum_freeze_strategy_threshold GUC (or reloption) with logged tables.
Tables that exceed the size threshold use the eager freezing strategy.
Unlogged tables and temp tables always use eager freezing strategy,
since the added cost is negligible there.  Non-permanent relations won't
incur any extra overhead in WAL written (for the obvious reason), nor in
pages dirtied (since any extra freezing will only take place on pages
whose PD_ALL_VISIBLE bit needed to be set either way).

VACUUM uses lazy freezing strategy for logged tables that fall under the
GUC size threshold.  Page-level freezing triggers based on the criteria
established in commit 1de58df4, which added basic page-level freezing.

Eager freezing is strictly more aggressive than lazy freezing.  Settings
like vacuum_freeze_min_age still get applied in just the same way in
every VACUUM, independent of the strategy in use.  The only mechanical
difference between eager and lazy freezing strategies is that only the
former applies its own additional criteria to trigger freezing pages.
Note that even lazy freezing strategy will trigger freezing whenever a
page happens to have required that an FPI be written during pruning,
provided that the page will thereby become all-frozen in the visibility
map afterwards (due to the FPI optimization from commit 1de58df4).

The vacuum_freeze_strategy_threshold default setting is 4GB.  This is a
relatively low setting that prioritizes performance stability.  It will
be reviewed at the end of the Postgres 16 beta period.

Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Jeff Davis <pgsql@j-davis.com>
Reviewed-By: Andres Freund <andres@anarazel.de>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-WzkFok_6EAHuK39GaW4FjEFQsY=3J0AAd6FXk93u-Xq3Fg@mail.gmail.com
2023-01-25 14:15:38 -08:00
Tom Lane 3b4ac33254 Avoid type cheats for invalid dsa_handles and dshash_table_handles.
Invent separate macros for "invalid" values of these types, so that
we needn't embed knowledge of their representations into calling code.
These are all zeroes anyway ATM, so this is not fixing any live bug,
but it makes the code cleaner and more future-proof.

I (tgl) also chose to move DSM_HANDLE_INVALID into dsm_impl.h,
since it seems like it should live beside the typedef for dsm_handle.

Hou Zhijie, Nathan Bossart, Kyotaro Horiguchi, Tom Lane

Discussion: https://postgr.es/m/OS0PR01MB5716860B1454C34E5B179B6694C99@OS0PR01MB5716.jpnprd01.prod.outlook.com
2023-01-25 11:48:38 -05:00
Thomas Munro 239b175342 Process pending postmaster work before connections.
Modify the new event loop code from commit 7389aad6 so that it checks
for work requested by signal handlers even if it doesn't see a latch
event yet.

This gives priority to shutdown and reload requests where the latch will
be reported later in the event array, or in a later call to
WaitEventSetWait(), due to scheduling details.  In particular, this
guarantees that a SIGHUP-then-connect sequence (as seen in
authentication tests) causes the postmaster to process the reload before
accepting the connection.  If the WaitEventSetWait() call saw the socket
as ready, and the reload signal was generated before the connection,
then the latest time the signal handler should be able to run is after
poll/epoll_wait/kevent returns but before we check the
pending_pm_reload_request flag.

While here, also shift the handling of child exit below reload requests,
per Tom Lane's observation that that might start new processes, so we
should make sure we pick up new settings first.

This probably explains the one-off failure of build farm animal
malleefowl.

Reported-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/OS0PR01MB57163D3BF2AB42ECAA94E5C394C29%40OS0PR01MB5716.jpnprd01.prod.outlook.com
2023-01-25 15:00:05 +13:00
Peter Geoghegan 8f8f115932 Update more obsolete multixact.c comments.
Update some remaining comments in multixact.c that still described SLRU
truncation as happening in the checkpointer, rather than during VACUUM.

Follow-up to commit 5212d447.

Shi yu, with tweaks by me.

Author: Shi yu <shiy.fnst@fujitsu.com>
Discussion: https://postgr.es/m/OSZPR01MB631066BF246F8F74E83222FCFDC69@OSZPR01MB6310.jpnprd01.prod.outlook.com
2023-01-24 15:15:33 -08:00
Robert Haas f1358ca52d Adjust interaction of CREATEROLE with role properties.
Previously, a CREATEROLE user without SUPERUSER could not alter
REPLICATION users in any way, and could not set the BYPASSRLS
attribute. However, they could manipulate the CREATEDB property
even if they themselves did not possess it.

With this change, a CREATEROLE user without SUPERUSER can set or
clear the REPLICATION, BYPASSRLS, or CREATEDB property on a new
role or a role that they have rights to manage if and only if
that property is set for their own role.

This implements the standard idea that you can't give permissions
you don't have (but you can give the ones you do have). We might
in the future want to provide more powerful ways to constrain
what a CREATEROLE user can do - for example, to limit whether
CONNECTION LIMIT can be set or the values to which it can be set -
but that is left as future work.

Patch by me, reviewed by Nathan Bossart, Tushar Ahuja, and Neha
Sharma.

Discussion: http://postgr.es/m/CA+TgmobX=LHg_J5aT=0pi9gJy=JdtrUVGAu0zhr-i5v5nNbJDg@mail.gmail.com
2023-01-24 10:57:09 -05:00
Amit Kapila 6c6d6ba3ee Fix the Drop Database hang.
The drop database command waits for the logical replication sync worker to
accept ProcSignalBarrier and the worker's slot creation waits for the drop
database to finish which leads to a deadlock. This happens because the
tablesync worker holds interrupts while creating a slot.

We prevent cancel/die interrupts while creating a slot in the table sync
worker because it is possible that before the server finishes this
command, a concurrent drop subscription happens which would complete
without removing this slot and that leads to the slot existing until the
end of walsender. However, the slot will eventually get dropped at the
walsender exit time, so there is no danger of the dangling slot.

This patch reallows cancel/die interrupts while creating a slot and
modifies the test to wait for slots to become zero to prevent finding an
ephemeral slot.

The reported hang doesn't happen in PG14 as the drop database starts to
wait for ProcSignalBarrier with PG15 (commits 4eb2176318 and e2f65f4255)
but it is good to backpatch this till PG14 as it is not a good idea to
prevent interrupts during a network call that could block indefinitely.

Reported-by: Lakshmi Narayanan Sreethar
Diagnosed-by: Andres Freund
Author: Hou Zhijie
Reviewed-by: Vignesh C, Amit Kapila
Backpatch-through: 14, where it was introduced in commit 6b67d72b60
Discussion: https://postgr.es/m/CA+kvmZELXQ4ZD3U=XCXuG3KvFgkuPoN1QrEj8c-rMRodrLOnsg@mail.gmail.com
2023-01-24 09:25:36 +05:30
Andres Freund 728f86fec6 libpqwalreceiver: Convert to libpq-be-fe-helpers.h
In contrast to the changes to dblink and postgres_fdw, this does not fix a
bug, as libpqwalreceiver did already process interrupts.

Besides reducing code duplication, the conversion leads to libpqwalreceiver
now using reserving file descriptors for libpq connections. While not strictly
required for the use in walreceiver, we are also using libpqwalreceiver for
logical replication, where it does seem more important.

Even if we eventually decide to backpatch the prior commits, there'd be no
need to backpatch this commit, due to not fixing an active bug.

Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20220925232237.p6uskba2dw6fnwj2@awork3.anarazel.de
2023-01-23 19:25:23 -08:00
Andres Freund bc54ef4ec2 Fix error handling in libpqrcv_connect()
When libpqrcv_connect (also known as walrcv_connect()) failed, it leaked the
libpq connection. In most paths that's fairly harmless, as the calling process
will exit soon after. But e.g. CREATE SUBSCRIPTION could lead to a somewhat
longer lived leak.

Fix by releasing resources, including the libpq connection, on error.

Add a test exercising the error code path. To make it reliable and safe, the
test tries to connect to port=-1, which happens to fail during connection
establishment, rather than during connection string parsing.

Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20230121011237.q52apbvlarfv6jm6@awork3.anarazel.de
Backpatch: 11-
2023-01-23 18:27:42 -08:00
Peter Eisentraut 8dd43894b1 Fix XLogPageRead() comment
7fcbf6a and 2ff6555 changed the function signature of XLogPageRead()
but did not update the comment.

XLogReaderRoutine contains up to date information about the API, so no
need to repeat all that at XLogPageRead(), but fix the mentions of the
no longer existing function arguments.
2023-01-23 21:46:30 +01:00
Dean Rasheed 6dfacbf72b Add non-decimal integer support to type numeric.
This enhances the numeric type input function, adding support for
hexadecimal, octal, and binary integers of any size, up to the limits
of the numeric type.

Since 6fcda9aba8, such non-decimal integers have been accepted by the
parser as integer literals and passed through to numeric_in(). This
commit gives numeric_in() the ability to handle them.

While at it, simplify the handling of NaN and infinities, reducing the
number of calls to pg_strncasecmp(), and arrange for pg_strncasecmp()
to not be called at all for regular numbers. This gives a significant
performance improvement for decimal inputs, more than offsetting the
small performance hit of checking for non-decimal input.

Discussion: https://postgr.es/m/CAEZATCV8XShnmT9HZy25C%2Bo78CVOFmUN5EM9FRAZ5xvYTggPMg%40mail.gmail.com
2023-01-23 19:21:22 +00:00
Dean Rasheed 0aa38db56b Optimise numeric division for 3 and 4 base-NBASE digit divisors.
On platforms with 128-bit integer support, introduce a new function
div_var_int64(), along the same lines as div_var_int() added in
d1b307eef2 for divisors with 1 or 2 base-NBASE digits, and use it to
speed up div_var() and div_var_fast() in a similar way when the
divisor has 3 or 4 base-NBASE digits.

This gives significant performance gains for divisors with 9-16
decimal digits.

Joel Jacobson.

Discussion:
  https://postgr.es/m/b7a5893d-af18-4c0b-8918-96de5f1bbf39%40app.fastmail.com
  https://postgr.es/m/CAEZATCXGm%3DDyTq%3DFrcOqC0gPMVveKUYTaD5KRRoajrUTiWxVMw%40mail.gmail.com
2023-01-23 11:58:28 +00:00
David Rowley 009dbdea02 Run pgindent on heapam.c
An upcoming patch by Melanie Plageman does some refactoring work in this
area.  Run pgindent on that file now before making any changes so that
it's easier to maintain/evolve each of the individual patches doing the
refactor work.  Additionally, add a few new required typedefs to the list
to make it easier to do future pgindent runs on this file during the
refactor work.

Discussion: https://postgr.es/m/CAAKRu_YSOnhKsDyFcqJsKtBSrd32DP-jjXmv7hL0BPD-z0TGXQ@mail.gmail.com
2023-01-23 23:08:38 +13:00
Heikki Linnakangas 236f1ea84c Fix and clarify function comment on LogicalTapeSetCreate.
Commit c4649cce39 removed the "shared" and "ntapes" arguments, but the
comment still talked about "shared". It also talked about "a shared
file handle", which was technically correct because even before commit
c4649cce39, the "shared file handle" referred to the "fileset"
argument, not "shared". But it was very confusing. Improve the
comment.

Also add a comment on what the "preallocate" argument does.

Backpatch to v15, just to make backpatching other patches easier in
the future.

Discussion: https://www.postgresql.org/message-id/af989685-91d5-aad4-8f60-1d066b5ec309@enterprisedb.com
Reviewed-by: Peter Eisentraut
2023-01-23 11:56:43 +02:00
David Rowley 16fd03e956 Allow parallel aggregate on string_agg and array_agg
This adds combine, serial and deserial functions for the array_agg() and
string_agg() aggregate functions, thus allowing these aggregates to
partake in partial aggregations.  This allows both parallel aggregation to
take place when these aggregates are present and also allows additional
partition-wise aggregation plan shapes to include plans that require
additional aggregation once the partially aggregated results from the
partitions have been combined.

Author: David Rowley
Reviewed-by: Andres Freund, Tomas Vondra, Stephen Frost, Tom Lane
Discussion: https://postgr.es/m/CAKJS1f9sx_6GTcvd6TMuZnNtCh0VhBzhX6FZqw17TgVFH-ga_A@mail.gmail.com
2023-01-23 17:35:01 +13:00
Tom Lane 5a3a95385b Track logrep apply workers' last start times to avoid useless waits.
Enforce wal_retrieve_retry_interval on a per-subscription basis,
rather than globally, and arrange to skip that delay in case of
an intentional worker exit.  This probably makes little difference
in the field, where apply workers wouldn't be restarted often;
but it has a significant impact on the runtime of our logical
replication regression tests (even though those tests use
artificially-small wal_retrieve_retry_interval settings already).

Nathan Bossart, with mostly-cosmetic editorialization by me

Discussion: https://postgr.es/m/20221122004119.GA132961@nathanxps13
2023-01-22 14:08:46 -05:00
Tom Lane c9f7f92648 Allow REPLICA IDENTITY to be set on an index that's not (yet) valid.
The motivation for this change is that when pg_dump dumps a
partitioned index that's marked REPLICA IDENTITY, it generates a
command sequence that applies REPLICA IDENTITY before the partitioned
index has been marked valid, causing restore to fail.  We could
perhaps change pg_dump to not do it like that, but that would be
difficult and would not fix existing dump files with the problem.
There seems to be very little reason for the backend to disallow
this anyway --- the code ignores indisreplident when the index
isn't valid --- so instead let's fix it by allowing the case.

Commit 9511fb37a previously expressed a concern that allowing
indisreplident to be set on invalid indexes might allow us to
wind up in a situation where a table could have indisreplident
set on multiple indexes.  I'm not sure I follow that concern
exactly, but in any case the only way that could happen is because
relation_mark_replica_identity is too trusting about the existing set
of markings being valid.  Let's just rip out its early-exit code path
(which sure looks like premature optimization anyway; what are we
doing expending code to make redundant ALTER TABLE ... REPLICA
IDENTITY commands marginally faster and not-redundant ones marginally
slower?) and fix it to positively guarantee that no more than one
index is marked indisreplident.

The pg_dump failure can be demonstrated in all supported branches,
so back-patch all the way.  I chose to back-patch 9511fb37a as well,
just to keep indisreplident handling the same in all branches.

Per bug #17756 from Sergey Belyashov.

Discussion: https://postgr.es/m/17756-dd50e8e0c8dd4a40@postgresql.org
2023-01-21 13:10:29 -05:00
Noah Misch e52daaabf8 Reject CancelRequestPacket having unexpected length.
When the length was too short, the server read outside the allocation.
That yielded the same log noise as sending the correct length with
(backendPID,cancelAuthCode) matching nothing.  Change to a message about
the unexpected length.  Given the attacker's lack of control over the
memory layout and the general lack of diversity in memory layouts at the
code in question, we doubt a would-be attacker could cause a segfault.
Hence, while the report arrived via security@postgresql.org, this is not
a vulnerability.  Back-patch to v11 (all supported versions).

Andrey Borodin, reviewed by Tom Lane.  Reported by Andrey Borodin.
2023-01-21 06:08:00 -08:00
Andres Freund 25b2aba0c3 Zero initialize uses of instr_time about to trigger compiler warnings
These are all not necessary from a correctness POV. However, in the near
future instr_time will be simplified to an int64, at which point gcc would
otherwise start to warn about the changed places.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20230116023639.rn36vf6ajqmfciua@awork3.anarazel.de
2023-01-20 21:16:47 -08:00
Michael Paquier 8eba3e3f02 Move queryjumble.c code to src/backend/nodes/
This will ease a follow-up move that will generate automatically this
code.  The C file is renamed, for consistency with the node-related
files whose code are generated by gen_node_support.pl:
- queryjumble.c -> queryjumblefuncs.c
- utils/queryjumble.h -> nodes/queryjumble.h

Per a suggestion from Peter Eisentraut.

Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/Y5BHOUhX3zTH/ig6@paquier.xyz
2023-01-21 11:48:37 +09:00
Robert Haas 6e2775e4d4 Add new GUC reserved_connections.
This provides a way to reserve connection slots for non-superusers.
The slots reserved via the new GUC are available only to users who
have the new predefined role pg_use_reserved_connections.
superuser_reserved_connections remains as a final reserve in case
reserved_connections has been exhausted.

Patch by Nathan Bossart. Reviewed by Tushar Ahuja and by me.

Discussion: http://postgr.es/m/20230119194601.GA4105788@nathanxps13
2023-01-20 15:39:13 -05:00
Robert Haas fe00fec1f5 Rename ReservedBackends variable to SuperuserReservedConnections.
This is in preparation for adding a new reserved_connections GUC,
but aligning the GUC name with the variable name is also a good
idea on general principle.

Patch by Nathan Bossart. Reviewed by Tushar Ahuja and by me.

Discussion: http://postgr.es/m/20230119194601.GA4105788@nathanxps13
2023-01-20 15:32:08 -05:00
Robert Haas 6c1d5ba486 Update docs and error message for superuser_reserved_connections.
Commit ea92368cd1 made max_wal_senders
a separate pool of backends from max_connections, but the documentation
and error message for superuser_reserved_connections weren't updated
at the time, and as a result are somewhat misleading. Update.

This is arguably a back-patchable bug fix, but because it seems quite
minor, no back-patch.

Patch by Nathan Bossart. Reviewed by Tushar Ahuja and by me.

Discussion: http://postgr.es/m/20230119194601.GA4105788@nathanxps13
2023-01-20 15:23:04 -05:00
Andres Freund d137cb52cb Remove SHM_QUEUE
Prior patches got rid of all the uses of SHM_QUEUE. ilist.h style lists are
more widely used and have an easier to use interface. As there are no users
left, remove SHM_QUEUE.

Reviewed-by: Thomas Munro <thomas.munro@gmail.com> (in an older version)
Discussion: https://postgr.es/m/20221120055930.t6kl3tyivzhlrzu2@awork3.anarazel.de
Discussion: https://postgr.es/m/20200211042229.msv23badgqljrdg2@alap3.anarazel.de
2023-01-19 18:55:51 -08:00
Andres Freund 9600371764 Use dlists instead of SHM_QUEUE for predicate locking
Part of a series to remove SHM_QUEUE. ilist.h style lists are more widely used
and have an easier to use interface.

Reviewed-by: Thomas Munro <thomas.munro@gmail.com> (in an older version)
Discussion: https://postgr.es/m/20221120055930.t6kl3tyivzhlrzu2@awork3.anarazel.de
Discussion: https://postgr.es/m/20200211042229.msv23badgqljrdg2@alap3.anarazel.de
2023-01-19 18:55:51 -08:00