This set of commits has some bugs with known fixes, but at this late
stage in the release cycle it seems best to revert and resubmit next
time, along with some new automated test coverage for this whole area.
Commits reverted:
dc88460c: Doc: Review for "Optionally prefetch referenced data in recovery."
1d257577: Optionally prefetch referenced data in recovery.
f003d9f8: Add circular WAL decoding buffer.
323cbe7c: Remove read_page callback from XLogReader.
Remove the new GUC group WAL_RECOVERY recently added by a55a9847, as the
corresponding section of config.sgml is now reverted.
Discussion: https://postgr.es/m/CAOuzzgrn7iKnFRsB4MHp3UisEQAGgZMbk_ViTN4HV4-Ksq8zCg%40mail.gmail.com
It seems that various people have moved GUCs around in the config.sgml
listing without bothering to make the code agree. Ensure that the
config_group codes assigned to GUCs match where they are listed in
config.sgml. Likewise ensure that postgresql.conf.sample lists GUCs
in the same sub-section and same ordering as they appear in config.sgml.
(I've got some doubts about some of these choices, but for the purposes
of this patch, we'll treat config.sgml as gospel.)
Notably, this requires adding a WAL_RECOVERY config_group value,
because 1d257577e didn't. As long as we're renumbering that enum
anyway, let's take out the values corresponding to major groups
that are divided into sub-groups. No GUC should be assigned to the
major group itself, so those values just create a temptation to
do the wrong thing, while adding work for translators.
In passing, adjust the short_desc strings for PRESET_OPTIONS GUCs
to uniformly use the phrasing "Shows XYZ.", removing the impression
some of these strings left that you can set the value.
While some of these errors are old, no back-patch, as changing the
contents of the pg_settings view in stable branches seems more likely
to be seen as a compatibility break than anything helpful.
Bharath Rupireddy, Justin Pryzby, Tom Lane
Discussion: https://postgr.es/m/16997-ff16127f6e0d1390@postgresql.org
Discussion: https://postgr.es/m/20210413123139.GE6091@telsasoft.com
The usual behavior for functions in ruleutils.c is to return NULL when
the object does not exist. pg_get_statisticsobjdef_expressions raised an
error instead, so correct that.
Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20210505210947.GA27406%40telsasoft.com
Design problems were discovered in the handling of composite types and
record types that would cause some relevant versions not to be recorded.
Misgivings were also expressed about the use of the pg_depend catalog
for this purpose. We're out of time for this release so we'll revert
and try again.
Commits reverted:
1bf946bd: Doc: Document known problem with Windows collation versions.
cf002008: Remove no-longer-relevant test case.
ef387bed: Fix bogus collation-version-recording logic.
0fb0a050: Hide internal error for pg_collation_actual_version(<bad OID>).
ff942057: Suppress "warning: variable 'collcollate' set but not used".
d50e3b1f: Fix assertion in collation version lookup.
f24b1569: Rethink extraction of collation dependencies.
257836a7: Track collation versions for indexes.
cd6f479e: Add pg_depend.refobjversion.
7d1297df: Remove pg_collation.collversion.
Discussion: https://postgr.es/m/CA%2BhUKGLhj5t1fcjqAu8iD9B3ixJtsTNqyCCD4V0aTO9kAKAjjA%40mail.gmail.com
Properly fix:
- the "ONLY" in FROM [ONLY] isn't hashed
- the agglevelsup field in GROUPING isn't hashed
- WITH TIES not being hashed (new in PG 13)
- "DISTINCT" in "GROUP BY [DISTINCT]" isn't hashed (new in PG 14)
Reported-by: Julien Rouhaud
Discussion: https://postgr.es/m/20210425081119.ulyzxqz23ueh3wuj@nol
websearch_to_tsquery() splits text in quotes into tokens and connects them with
phrase operator on its own. However, that leads to surprising results when the
token contains no words.
For instance, websearch_to_tsquery('"aaa: bbb"') is 'aaa <2> bbb', because
it is equivalent of to_tsquery(E'aaa <-> \':\' <-> bbb'). But
websearch_to_tsquery('"aaa: bbb"') has to be 'aaa <-> bbb' in order to match
to_tsvector('aaa: bbb').
Since 0c4f355c6a, we anyway connect lexemes of complex tokens with phrase
operators. Thus, let's just websearch_to_tsquery() parse text in quotes as
a single token. Therefore, websearch_to_tsquery() should process the quoted
text in the same way phraseto_tsquery() does. This solution is what we exactly
need and also simplifies the code.
This commit is an incompatible change, so we don't backpatch it.
Reported-by: Valentin Gatien-Baron
Discussion: https://postgr.es/m/CA%2B0DEqiZs7gdOd4ikmg%3D0UWG%2BSwWOLxPsk_JW-sx9WNOyrb0KQ%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Tom Lane, Zhihong Yu
Makes partition descriptor acquisition faster during the transient
period in which a partition is in the process of being detached.
This also adds the restriction that only one partition can be in
pending-detach state for a partitioned table.
While at it, return find_inheritance_children() API to what it was
before 71f4c8c6f7, and create a separate
find_inheritance_children_extended() that returns detailed info about
detached partitions.
(This incidentally fixes a bug in 8aba932251 whereby a memory context
holding a transient partdesc is reparented to a NULL PortalContext,
leading to permanent leak of that memory. The fix is to no longer rely
on reparenting contexts to PortalContext. Reported by Amit Langote.)
Per gripe from Amit Langote
Discussion: https://postgr.es/m/CA+HiwqFgpP1LxJZOBYGt9rpvTjXXkg5qG2+Xch2Z1Q7KrqZR1A@mail.gmail.com
Previously, we used to use the array of size max_replication_slots to
store stats for replication slots. But that had two problems in the cases
where a message for dropping a slot gets lost: 1) the stats for the new
slot are not recorded if the array is full and 2) writing beyond the end
of the array if the user reduces the max_replication_slots.
This commit uses HTAB for replication slot statistics, resolving both
problems. Now, pgstat_vacuum_stat() search for all the dead replication
slots in stats hashtable and tell the collector to remove them. To avoid
showing the stats for the already-dropped slots, pg_stat_replication_slots
view searches slot stats by the slot name taken from pg_replication_slots.
Also, we send a message for creating a slot at slot creation, initializing
the stats. This reduces the possibility that the stats are accumulated
into the old slot stats when a message for dropping a slot gets lost.
Reported-by: Andres Freund
Author: Sawada Masahiko, test case by Vignesh C
Reviewed-by: Amit Kapila, Vignesh C, Dilip Kumar
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
The Truncate operation acquires an exclusive lock on the target relation
and indexes. It then waits for logical replication of the operation to
finish at commit. Now because we are acquiring the shared lock on the
target index to get index attributes in pgoutput while sending the
changes for the Truncate operation, it leads to a deadlock.
Actually, we don't need to acquire a lock on the target index as we build
the cache entry using a historic snapshot and all the later changes are
absorbed while decoding WAL. So, we wrote a special purpose function for
logical replication to get a bitmap of replica identity attribute numbers
where we get that information without locking the target index.
We decided not to backpatch this as there doesn't seem to be any field
complaint about this issue since it was introduced in commit 5dfd1e5a in
v11.
Reported-by: Haiying Tang
Author: Takamichi Osumi, test case by Li Japin
Reviewed-by: Amit Kapila, Ajin Cherian
Discussion: https://postgr.es/m/OS0PR01MB6113C2499C7DC70EE55ADB82FB759@OS0PR01MB6113.jpnprd01.prod.outlook.com
These functions shouldn't receive null arguments: multirange_constructor0()
doesn't have any arguments while multirange_constructor2() has a single array
argument, which is never null.
But mark them strict anyway for the sake of uniformity.
Also, make checks for null arguments use elog() instead of ereport() as these
errors should normally be never thrown. And adjust corresponding comments.
Catversion is bumped.
Reported-by: Peter Eisentraut
Discussion: https://postgr.es/m/0f783a96-8d67-9e71-996b-f34a7352eeef%40enterprisedb.com
log_statement is issued before query_id can be computed, so properly
clear the value, and document the interaction.
Reported-by: Fujii Masao, Michael Paquier
Discussion: https://postgr.es/m/YHPkU8hFi4no4NSw@paquier.xyz
Author: Julien Rouhaud
Previously, it was pg_stat_activity.queryid to match the
pg_stat_statements queryid column. This is an adjustment to patch
4f0b0966c8. This also adjusts some of the internal function calls to
match. Catversion bumped.
Reported-by: Álvaro Herrera, Julien Rouhaud
Discussion: https://postgr.es/m/20210408032704.GA7498@alvherre.pgsql
This adds the statistics about total transactions count and total
transaction data logically sent to the decoding output plugin from
ReorderBuffer. Users can query the pg_stat_replication_slots view to check
these stats.
Suggested-by: Andres Freund
Author: Vignesh C and Amit Kapila
Reviewed-by: Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
This GUC has always been classified as a planner option since its
introduction in 7c944bd, and was listed in postgresql.conf.sample. As
this parameter exists for testing purposes, move it to the section
dedicated to developer parameters and hence remove it from
postgresql.conf.sample. This will avoid any temptation to play with it
on production servers for users that should never really have to touch
this parameter.
The general description used for developer options is reworded a bit, to
take into account the inclusion of force_parallel_mode, per a suggestion
from Tom Lane.
Per discussion between Tom Lane, Bruce Momjian, Justin Pryzby, Bharath
Rupireddy and me.
Author: Justin Pryzby, Tom Lane
Discussion: https://postgr.es/m/20210403152402.GA8049@momjian.us
This will make it consistent with the other usage of slotname in the code.
In the passing, change pgstat_report_replslot signature to use a structure
rather than multiple parameters.
Reported-by: Andres Freund
Author: Vignesh C
Reviewed-by: Sawada Masahiko, Amit Kapila
Discussion: https://postgr.es/m/20210319185247.ldebgpdaxsowiflw@alap3.anarazel.de
Most GUC check hooks that inspect database state have special checks
that prevent them from throwing hard errors for state-dependent issues
when source == PGC_S_TEST. This allows, for example,
"ALTER DATABASE d SET default_text_search_config = foo" when the "foo"
configuration hasn't been created yet. Without this, we have problems
during dump/reload or pg_upgrade, because pg_dump has no idea about
possible dependencies of GUC values and can't ensure a safe restore
ordering.
However, check_role() and check_session_authorization() hadn't gotten
the memo about that, and would throw hard errors anyway. It's not
entirely clear what is the use-case for "ALTER ROLE x SET role = y",
but we've now heard two independent complaints about that bollixing
an upgrade, so apparently some people are doing it.
Hence, fix these two functions to act more like other check hooks
with similar needs. (But I did not change their insistence on
being inside a transaction, as it's still not apparent that setting
either GUC from the configuration file would be wise.)
Also fix check_temp_buffers, which had a different form of the disease
of making state-dependent checks without any exception for PGC_S_TEST.
A cursory survey of other GUC check hooks did not find any more issues
of this ilk. (There are a lot of interdependencies among
PGC_POSTMASTER and PGC_SIGHUP GUCs, which may be a bad idea, but
they're not relevant to the immediate concern because they can't be
set via ALTER ROLE/DATABASE.)
Per reports from Charlie Hornsby and Nathan Bossart. Back-patch
to all supported branches.
Discussion: https://postgr.es/m/HE1P189MB0523B31598B0C772C908088DB7709@HE1P189MB0523.EURP189.PROD.OUTLOOK.COM
Discussion: https://postgr.es/m/20160711223641.1426.86096@wrigleys.postgresql.org
With the Oracle Developer Studio 12.6 compiler, #line directives alter
the current source file location for purposes of #include "..."
directives. Hence, a VPATH build failed with 'cannot find include file:
"specscanner.c"'. With two exceptions, parser-containing directories
already add "-I. -I$(srcdir)"; eliminate the exceptions. Back-patch to
9.6 (all supported versions).
This GUC has already been classified as LOGGING_WHAT, but its location
in postgresql.conf.sample and the documentation did not reflect that, so
fix those inconsistencies.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20210404012546.GK6592@telsasoft.com
Using Roman numbers (via "RM" or "rm") for a conversion to calculate a
number of months has never considered the case of negative numbers,
where a conversion could easily cause out-of-bound memory accesses. The
conversions in themselves were not completely consistent either, as
specifying 12 would result in NULL, but it should mean XII.
This commit reworks the conversion calculation to have a more
consistent behavior:
- If the number of months and years is 0, return NULL.
- If the number of months is positive, return the exact month number.
- If the number of months is negative, do a backward calculation, with
-1 meaning December, -2 November, etc.
Reported-by: Theodor Arsenij Larionov-Trichkin
Author: Julien Rouhaud
Discussion: https://postgr.es/m/16953-f255a18f8c51f1d5@postgresql.org
backpatch-through: 9.6
Coverity complained about possible overflow in expressions like
intresult = tm->tm_sec * 1000000 + fsec;
on the grounds that the multiplication would happen in 32-bit
arithmetic before widening to the int64 result. I think these
are all false positives because of the limited possible range of
tm_sec; but nonetheless it seems silly to spell it like that when
nearby lines have the identical computation written with a 64-bit
constant.
... or more accurately, with an LL constant, which is not project
style. Make all of these use INT64CONST(), as we do elsewhere.
This is all new code from a2da77cdb, so no need for back-patch.
Commit c9c41c7a33 used two different
naming patterns. Standardize on the majority pattern, which was the
only pattern in the last reviewed version of that commit.
Comment fixes are applied on HEAD, and documentation improvements are
applied on back-branches where needed.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20210408164008.GJ6592@telsasoft.com
Backpatch-through: 9.6
Ignore parallel workers in pg_stat_statements
Oversight in 4f0b0966c8 which exposed queryid in parallel workers.
Counters are aggregated by the main backend process so parallel workers
would report duplicated activity, and could also report activity for the
wrong entry as they are only aware of the top level queryid.
Fix thinko in pg_stat_get_activity when retrieving the queryid.
Remove unnecessary call to pgstat_report_queryid().
Reported-by: Amit Kapila, Andres Freund, Thomas Munro
Discussion: https://postgr.es/m/20210408051735.lfbdzun5zdlax5gd@alap3.anarazel.dep634GTSOqnDW86Owrn6qDAVosC5dJjXjp7BMfc5Gz1Q@mail.gmail.com
Author: Julien Rouhaud
Introduce a new GUC recovery_prefetch, disabled by default. When
enabled, look ahead in the WAL and try to initiate asynchronous reading
of referenced data blocks that are not yet cached in our buffer pool.
For now, this is done with posix_fadvise(), which has several caveats.
Better mechanisms will follow in later work on the I/O subsystem.
The GUC maintenance_io_concurrency is used to limit the number of
concurrent I/Os we allow ourselves to initiate, based on pessimistic
heuristics used to infer that I/Os have begun and completed.
The GUC wal_decode_buffer_size is used to limit the maximum distance we
are prepared to read ahead in the WAL to find uncached blocks.
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com> (parts)
Reviewed-by: Andres Freund <andres@anarazel.de> (parts)
Reviewed-by: Tomas Vondra <tomas.vondra@2ndquadrant.com> (parts)
Tested-by: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Tested-by: Jakub Wartak <Jakub.Wartak@tomtom.com>
Tested-by: Dmitry Dolgov <9erthalion6@gmail.com>
Tested-by: Sait Talha Nisanci <Sait.Nisanci@microsoft.com>
Discussion: https://postgr.es/m/CA%2BhUKGJ4VJN8ttxScUFM8dOKX0BrBiboo5uz1cq%3DAovOddfHpA%40mail.gmail.com
This adds a function, pg_wait_for_backend_termination(), and a new
timeout argument to pg_terminate_backend(), which will wait for the
backend to actually terminate (with or without signaling it to do so
depending on which function is called). The default behaviour of
pg_terminate_backend() remains being timeout=0 which does not waiting.
For pg_wait_for_backend_termination() the default wait is 5 seconds.
Author: Bharath Rupireddy
Reviewed-By: Fujii Masao, David Johnston, Muhammad Usama,
Hou Zhijie, Magnus Hagander
Discussion: https://postgr.es/m/CALj2ACUBpunmyhYZw-kXCYs5NM+h6oG_7Df_Tn4mLmmUQifkqA@mail.gmail.com
This adds support for writing CREATE FUNCTION and CREATE PROCEDURE
statements for language SQL with a function body that conforms to the
SQL standard and is portable to other implementations.
Instead of the PostgreSQL-specific AS $$ string literal $$ syntax,
this allows writing out the SQL statements making up the body
unquoted, either as a single statement:
CREATE FUNCTION add(a integer, b integer) RETURNS integer
LANGUAGE SQL
RETURN a + b;
or as a block
CREATE PROCEDURE insert_data(a integer, b integer)
LANGUAGE SQL
BEGIN ATOMIC
INSERT INTO tbl VALUES (a);
INSERT INTO tbl VALUES (b);
END;
The function body is parsed at function definition time and stored as
expression nodes in a new pg_proc column prosqlbody. So at run time,
no further parsing is required.
However, this form does not support polymorphic arguments, because
there is no more parse analysis done at call time.
Dependencies between the function and the objects it uses are fully
tracked.
A new RETURN statement is introduced. This can only be used inside
function bodies. Internally, it is treated much like a SELECT
statement.
psql needs some new intelligence to keep track of function body
boundaries so that it doesn't send off statements when it sees
semicolons that are inside a function body.
Tested-by: Jaime Casanova <jcasanov@systemguards.com.ec>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/1c11f1eb-f00c-43b7-799d-2d44132c02d7@2ndquadrant.com
Add a failsafe mechanism that is triggered by VACUUM when it notices
that the table's relfrozenxid and/or relminmxid are dangerously far in
the past. VACUUM checks the age of the table dynamically, at regular
intervals.
When the failsafe triggers, VACUUM takes extraordinary measures to
finish as quickly as possible so that relfrozenxid and/or relminmxid can
be advanced. VACUUM will stop applying any cost-based delay that may be
in effect. VACUUM will also bypass any further index vacuuming and heap
vacuuming -- it only completes whatever remaining pruning and freezing
is required. Bypassing index/heap vacuuming is enabled by commit
8523492d, which made it possible to dynamically trigger the mechanism
already used within VACUUM when it is run with INDEX_CLEANUP off.
It is expected that the failsafe will almost always trigger within an
autovacuum to prevent wraparound, long after the autovacuum began.
However, the failsafe mechanism can trigger in any VACUUM operation.
Even in a non-aggressive VACUUM, where we're likely to not advance
relfrozenxid, it still seems like a good idea to finish off remaining
pruning and freezing. An aggressive/anti-wraparound VACUUM will be
launched immediately afterwards. Note that the anti-wraparound VACUUM
that follows will itself trigger the failsafe, usually before it even
begins its first (and only) pass over the heap.
The failsafe is controlled by two new GUCs: vacuum_failsafe_age, and
vacuum_multixact_failsafe_age. There are no equivalent reloptions,
since that isn't expected to be useful. The GUCs have rather high
defaults (both default to 1.6 billion), and are expected to generally
only be used to make the failsafe trigger sooner/more frequently.
Author: Masahiko Sawada <sawada.mshk@gmail.com>
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAD21AoD0SkE11fMw4jD4RENAwBMcw1wasVnwpJVw3tVqPOQgAw@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzmgH3ySGYeC-m-eOBsa2=sDwa292-CFghV4rESYo39FsQ@mail.gmail.com
Use the in-core query id computation for pg_stat_activity,
log_line_prefix, and EXPLAIN VERBOSE.
Similar to other fields in pg_stat_activity, only the queryid from the
top level statements are exposed, and if the backends status isn't
active then the queryid from the last executed statements is displayed.
Add a %Q placeholder to include the queryid in log_line_prefix, which
will also only expose top level statements.
For EXPLAIN VERBOSE, if a query identifier has been computed, either by
enabling compute_query_id or using a third-party module, display it.
Bump catalog version.
Discussion: https://postgr.es/m/20210407125726.tkvjdbw76hxnpwfi@nol
Author: Julien Rouhaud
Reviewed-by: Alvaro Herrera, Nitin Jadhav, Zhihong Yu
Add compute_query_id GUC to control whether a query identifier should be
computed by the core (off by default). It's thefore now possible to
disable core queryid computation and use pg_stat_statements with a
different algorithm to compute the query identifier by using a
third-party module.
To ensure that a single source of query identifier can be used and is
well defined, modules that calculate a query identifier should throw an
error if compute_query_id specified to compute a query id and if a query
idenfitier was already calculated.
Discussion: https://postgr.es/m/20210407125726.tkvjdbw76hxnpwfi@nol
Author: Julien Rouhaud
Reviewed-by: Alvaro Herrera, Nitin Jadhav, Zhihong Yu
Formerly we were pretty lax about what a custom GUC's name could
be; so long as it had at least one dot in it, we'd take it.
However, corner cases such as dashes or equal signs in the name
would cause various bits of functionality to misbehave. Rather
than trying to make the world perfectly safe for that, let's
just require that custom names look like "identifier.identifier",
where "identifier" means something that scan.l would accept
without double quotes.
Along the way, this patch refactors things slightly in guc.c
so that find_option() is responsible for reporting GUC-not-found
cases, allowing removal of duplicative code from its callers.
Per report from Hubert Depesz Lubaczewski. No back-patch,
since the consequences of the problem don't seem to warrant
changing behavior in stable branches.
Discussion: https://postgr.es/m/951335.1612910077@sss.pgh.pa.us
Andrew Gierth reported that it's possible to crash the backend if no
pg_attrdef record is found to match an attribute that has atthasdef set.
AttrDefaultFetch warns about this situation, but then leaves behind
a relation tupdesc that has null "adbin" pointer(s), which most places
don't guard against.
We considered promoting the warning to an error, but throwing errors
during relcache load is pretty drastic: it effectively locks one out
of using the relation at all. What seems better is to leave the
load-time behavior as a warning, but then throw an error in any code
path that wants to use a default and can't find it. This confines
the error to a subset of INSERT/UPDATE operations on the table, and
in particular will at least allow a pg_dump to succeed.
Also, we should fix AttrDefaultFetch to not leave any null pointers
in the tupdesc, because that just creates an untested bug hazard.
While at it, apply the same philosophy of "warn at load, throw error
only upon use of the known-missing info" to CHECK constraints.
CheckConstraintFetch is very nearly the same logic as AttrDefaultFetch,
but for reasons lost in the mists of time, it was throwing ERROR for
the same cases that AttrDefaultFetch treats as WARNING. Make the two
functions more nearly alike.
In passing, get rid of potentially-O(N^2) loops in equalTupleDesc
by making AttrDefaultFetch sort the entries after fetching them,
so that equalTupleDesc can assume that entries in two equal tupdescs
must be in matching order. (CheckConstraintFetch already was sorting
CHECK constraints, but equalTupleDesc hadn't been told about it.)
There's some argument for back-patching this, but with such a small
number of field reports, I'm content to fix it in HEAD.
Discussion: https://postgr.es/m/87pmzaq4gx.fsf@news-spur.riddles.org.uk
The previous implementation of EXTRACT mapped internally to
date_part(), which returned type double precision (since it was
implemented long before the numeric type existed). This can lead to
imprecise output in some cases, so returning numeric would be
preferrable. Changing the return type of an existing function is a
bit risky, so instead we do the following: We implement a new set of
functions, which are now called "extract", in parallel to the existing
date_part functions. They work the same way internally but use
numeric instead of float8. The EXTRACT construct is now mapped by the
parser to these new extract functions. That way, dumps of views
etc. from old versions (which would use date_part) continue to work
unchanged, but new uses will map to the new extract functions.
Additionally, the reverse compilation of EXTRACT now reproduces the
original syntax, using the new mechanism introduced in
40c24bfef9.
The following minor changes of behavior result from the new
implementation:
- The column name from an isolated EXTRACT call is now "extract"
instead of "date_part".
- Extract from date now rejects inappropriate field names such as
HOUR. It was previously mapped internally to extract from
timestamp, so it would silently accept everything appropriate for
timestamp.
- Return values when extracting fields with possibly fractional
values, such as second and epoch, now have the full scale that the
value has internally (so, for example, '1.000000' instead of just
'1').
Reported-by: Petr Fedorov <petr.fedorov@phystech.edu>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/42b73d2d-da12-ba9f-570a-420e0cce19d9@phystech.edu
Commit 3e98c0bafb added pg_backend_memory_contexts view to display
the memory contexts of the backend process. However its target process
is limited to the backend that is accessing to the view. So this is
not so convenient when investigating the local memory bloat of other
backend process. To improve this situation, this commit adds
pg_log_backend_memory_contexts() function that requests to log
the memory contexts of the specified backend process.
This information can be also collected by calling
MemoryContextStats(TopMemoryContext) via a debugger. But
this technique cannot be used in some environments because no debugger
is available there. So, pg_log_backend_memory_contexts() allows us to
see the memory contexts of specified backend more easily.
Only superusers are allowed to request to log the memory contexts
because allowing any users to issue this request at an unbounded rate
would cause lots of log messages and which can lead to denial of service.
On receipt of the request, at the next CHECK_FOR_INTERRUPTS(),
the target backend logs its memory contexts at LOG_SERVER_ONLY level,
so that these memory contexts will appear in the server log but not
be sent to the client. It logs one message per memory context.
Because if it buffers all memory contexts into StringInfo to log them
as one message, which may require the buffer to be enlarged very much
and lead to OOM error since there can be a large number of memory
contexts in a backend.
When a backend process is consuming huge memory, logging all its
memory contexts might overrun available disk space. To prevent this,
now this patch limits the number of child contexts to log per parent
to 100. As with MemoryContextStats(), it supposes that practical cases
where the log gets long will typically be huge numbers of siblings
under the same parent context; while the additional debugging value
from seeing details about individual siblings beyond 100 will not be large.
There was another proposed patch to add the function to return
the memory contexts of specified backend as the result sets,
instead of logging them, in the discussion. However that patch is
not included in this commit because it had several issues to address.
Thanks to Tatsuhito Kasahara, Andres Freund, Tom Lane, Tomas Vondra,
Michael Paquier, Kyotaro Horiguchi and Zhihong Yu for the discussion.
Bump catalog version.
Author: Atsushi Torikoshi
Reviewed-by: Kyotaro Horiguchi, Zhihong Yu, Fujii Masao
Discussion: https://postgr.es/m/0271f440ac77f2a4180e0e56ebd944d1@oss.nttdata.com
spg_box_quad_leaf_consistent unconditionally returned the leaf
datum as leafValue, even though in its usage for poly_ops that
value is of completely the wrong type.
In versions before 12, that was harmless because the core code did
nothing with leafValue in non-index-only scans ... but since commit
2a6368343, if we were doing a KNN-style scan, spgNewHeapItem would
unconditionally try to copy the value using the wrong datatype
parameters. Said copying is a waste of time and space if we're not
going to return the data, but it accidentally failed to fail until
I fixed the datatype confusion in ac9099fc1.
Hence, change spgNewHeapItem to not copy the datum unless we're
actually going to return it later. This saves cycles and dodges
the question of whether lossy opclasses are returning the right
type. Also change spg_box_quad_leaf_consistent to not return
data that might be of the wrong type, as insurance against
somebody introducing a similar bug into the core code in future.
It seems like a good idea to back-patch these two changes into
v12 and v13, although I'm afraid to change spgNewHeapItem's
mistaken idea of which datatype to use in those branches.
Per buildfarm results from ac9099fc1.
Discussion: https://postgr.es/m/3728741.1617381471@sss.pgh.pa.us
pgstat_report_wait_start() and pgstat_report_wait_end() required two
conditional branches so far. One to check if MyProc is NULL, the other to
check if pgstat_track_activities is set. As wait events are used around
comparatively lightweight operations, and are inlined (reducing branch
predictor effectiveness), that's not great.
The dependency on MyProc has a second disadvantage: Low-level subsystems, like
storage/file/fd.c, report wait events, but architecturally it is preferable
for them to not depend on inter-process subsystems like proc.h (defining
PGPROC). After this change including pgstat.h (nor obviously its
sub-components like backend_status.h, wait_event.h, ...) does not pull in IPC
related headers anymore.
These goals, efficiency and abstraction, are achieved by having
pgstat_report_wait_start/end() not interact with MyProc, but instead a new
my_wait_event_info variable. At backend startup it points to a local variable,
removing the need to check for MyProc being NULL. During process
initialization my_wait_event_info is redirected to MyProc->wait_event_info. At
shutdown this is reversed. Because wait event reporting now does not need to
know about where the wait event is stored, it does not need to know about
PGPROC anymore.
The removal of the branch for checking pgstat_track_activities is simpler:
Don't check anymore. The cost due to the branch are often higher than the
store - and even if not, pgstat_track_activities is rarely disabled.
The main motivator to commit this work now is that removing the (indirect)
pgproc.h include from pgstat.h simplifies a patch to move statistics reporting
to shared memory (which still has a chance to get into 14).
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/20210402194458.2vu324hkk2djq6ce@alap3.anarazel.de
Backend status (supporting pg_stat_activity) and command
progress (supporting pg_stat_progress*) related code is largely
independent from the rest of pgstat.[ch] (supporting views like
pg_stat_all_tables that accumulate data over time). See also
a333476b92.
This commit doesn't rename the function names to make the distinction
from the rest of pgstat_ clearer - that'd be more invasive and not
clearly beneficial. If we were to decide to do such a rename at some
point, it's better done separately from moving the code as well.
Robert's review was of an earlier version.
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/20210316195440.twxmlov24rr2nxrg@alap3.anarazel.de
Similarly to the cryptohash implementations, this refactors the existing
HMAC code into a single set of APIs that can be plugged with any crypto
libraries PostgreSQL is built with (only OpenSSL currently). If there
is no such libraries, a fallback implementation is available. Those new
APIs are designed similarly to the existing cryptohash layer, so there
is no real new design here, with the same logic around buffer bound
checks and memory handling.
HMAC has a dependency on cryptohashes, so all the cryptohash types
supported by cryptohash{_openssl}.c can be used with HMAC. This
refactoring is an advantage mainly for SCRAM, that included its own
implementation of HMAC with SHA256 without relying on the existing
crypto libraries even if PostgreSQL was built with their support.
This code has been tested on Windows and Linux, with and without
OpenSSL, across all the versions supported on HEAD from 1.1.1 down to
1.0.1. I have also checked that the implementations are working fine
using some sample results, a custom extension of my own, and doing
cross-checks across different major versions with SCRAM with the client
and the backend.
Author: Michael Paquier
Reviewed-by: Bruce Momjian
Discussion: https://postgr.es/m/X9m0nkEJEzIPXjeZ@paquier.xyz
Thomas Munro