Commit Graph

45404 Commits

Author SHA1 Message Date
Tom Lane
8ede2691d6 Include contrib modules in the temp installation even without REGRESS.
Now that we have TAP tests, a contrib module may have something useful
to do in "make check" even if it has no pg_regress-style regression
scripts, and hence no REGRESS setting.  But the TAP tests will fail,
or else test the wrong installed files, unless we install the contrib
module into the temp installation.  So move the bit about adding to
EXTRA_INSTALL so that it applies regardless.

We might want this in back branches in future, but for the moment
I only risked adding it to v11.

Discussion: https://postgr.es/m/12438.1535488750@sss.pgh.pa.us
2018-08-28 17:26:19 -04:00
Andrew Gierth
8bc6a301b2 postgres_fdw: don't push ORDER BY with no vars (bug #15352)
Commit aa09cd242 changed a condition in find_em_expr_for_rel from
being a bms_equal comparison of relids to bms_is_subset, in order to
support order by clauses on foreign joins. But this also allows
through the degenerate case of expressions with no Vars at all (and
hence empty relids), including integer constants which will be parsed
unexpectedly on the remote (viz. "ERROR: ORDER BY position 0 is not in
select list" as in the bug report).

Repair by adding an additional !bms_is_empty test.

Backpatch through to 9.6 where the aforementioned change was made.

Per bug #15352 from Maksym Boguk; analysis and patch by me.

Discussion: https://postgr.es/m/153518420278.1478.14875560810251994661@wrigleys.postgresql.org
2018-08-28 15:04:19 +01:00
Andrew Gierth
bc552b322f Avoid quadratic slowdown in regexp match/split functions.
regexp_matches, regexp_split_to_table and regexp_split_to_array all
work by compiling a list of match positions as character offsets (NOT
byte positions) in the source string.

Formerly, they then used text_substr to extract the matched text; but
in a multi-byte encoding, that counts the characters in the string,
and the characters needed to reach the starting byte position, on
every call. Accordingly, the performance degraded as the product of
the input string length and the number of match positions, such that
splitting a string of a few hundred kbytes could take many minutes.

Repair by keeping the wide-character copy of the input string
available (only in the case where encoding_max_length is not 1) after
performing the match operation, and extracting substrings from that
instead. This reduces the complexity to being linear in the number of
result bytes, discounting the actual regexp match itself (which is not
affected by this patch).

In passing, remove cleanup using retail pfree() which was obsoleted by
commit ff428cded (Feb 2008) which made cleanup of SRF multi-call
contexts automatic. Also increase (to ~134 million) the maximum number
of matches and provide an error message when it is reached.

Backpatch all the way because this has been wrong forever.

Analysis and patch by me; review by Kaiting Chen.

Discussion: https://postgr.es/m/87pnyn55qh.fsf@news-spur.riddles.org.uk

see also https://postgr.es/m/87lg996g4r.fsf@news-spur.riddles.org.uk
2018-08-28 12:17:37 +01:00
Peter Eisentraut
da793baca2 pg_verify_checksums: Message style improvements and NLS support
The source code was already set up for NLS support, so just a nls.mk
file needed to be added.  Also, fix the old problem of putting the int64
format specifier right into the string, which breaks NLS.
2018-08-28 11:49:35 +02:00
Peter Eisentraut
2657d4ea66 Fix snapshot leak warning for some procedures
The problem arises with the combination of CALL with output parameters
and doing a COMMIT inside the procedure.  When a CALL has output
parameters, the portal uses the strategy PORTAL_UTIL_SELECT instead of
PORTAL_MULTI_QUERY.  Using PORTAL_UTIL_SELECT causes the portal's
snapshot to be registered with the current resource
owner (portal->holdSnapshot); see
9ee1cf04ab for the reason.

Normally, PortalDrop() unregisters the snapshot.  If not, then
ResourceOwnerRelease() will print a warning about a snapshot leak on
transaction commit.  A transaction commit normally drops all
portals (PreCommit_Portals()), except the active portal.  So in case of
the active portal, we need to manually release the snapshot to avoid the
warning.

Reported-by: Prabhat Sahu <prabhat.sahu@enterprisedb.com>
Reviewed-by: Jonathan S. Katz <jkatz@postgresql.org>
2018-08-27 22:15:39 +02:00
Tom Lane
c5e235ff8a Fix missing dependency for pg_dump's ENABLE ROW LEVEL SECURITY items.
The archive should show a dependency on the item's table, but it failed
to include one.  This could cause failures in parallel restore due to
emitting ALTER TABLE ... ENABLE ROW LEVEL SECURITY before restoring
the table's data.  In practice the odds of a problem seem low, since
you would typically need to have set FORCE ROW LEVEL SECURITY as well,
and you'd also need a very high --jobs count to have any chance of this
happening.  That probably explains the lack of field reports.

Still, it's a bug, so back-patch to 9.5 where RLS was introduced.

Discussion: https://postgr.es/m/19784.1535390902@sss.pgh.pa.us
2018-08-27 15:11:12 -04:00
Thomas Munro
9ca2207990 Fix typos.
Author: David Rowley
Discussion: https://postgr.es/m/CAKJS1f8du35u5DprpykWvgNEScxapbWYJdHq%2Bz06Wj3Y2KFPbw%40mail.gmail.com
2018-08-27 09:34:35 +12:00
Tom Lane
f8fc5f5f50 Make syslogger more robust against failures in opening CSV log files.
The previous coding figured it'd be good enough to postpone opening
the first CSV log file until we got a message we needed to write there.
This is unsafe, though, because if the open fails we end up in infinite
recursion trying to report the failure.  Instead make the CSV log file
management code look as nearly as possible like the longstanding logic
for the stderr log file.  In particular, open it immediately at postmaster
startup (if enabled), or when we get a SIGHUP in which we find that
log_destination has been changed to enable CSV logging.

It seems OK to fail if a postmaster-start-time open attempt fails, as
we've long done for the stderr log file.  But we can't die if we fail
to open a CSV log file during SIGHUP, so we're still left with a problem.
In that case, write any output meant for the CSV log file to the stderr
log file.  (This will also cover race-condition cases in which backends
send CSV log data before or after we have the CSV log file open.)

This patch also fixes an ancient oversight that, if CSV logging was
turned off during a SIGHUP, we never actually closed the last CSV
log file.

In passing, remember to reset whereToSendOutput = DestNone during syslogger
start, since (unlike all other postmaster children) it's forked before the
postmaster has done that.  This made for a platform-dependent difference
in error reporting behavior between the syslogger and other children:
except on Windows, it'd report problems to the original postmaster stderr
as well as the normal error log file(s).  It's barely possible that that
was intentional at some point; but it doesn't seem likely to be desirable
in production, and the platform dependency definitely isn't desirable.

Per report from Alexander Kukushkin.  It's been like this for a long time,
so back-patch to all supported branches.

Discussion: https://postgr.es/m/CAFh8B==iLUD_gqC-dAENS0V+kVrCeGiKujtKqSQ7++S-caaChw@mail.gmail.com
2018-08-26 14:21:55 -04:00
Bruce Momjian
231cf30e98 doc: "Latest checkpoint location" will not match in pg_upgrade
Mention that "Latest checkpoint location" will not match in pg_upgrade
if the standby server is still running during the upgrade, which is
possible.  "Match" text first appeared in PG 9.5.

Reported-by: Paul Bonaud

Discussion: https://postgr.es/m/c7268794-edb4-1772-3bfd-04c54585c24e@trainline.com

Backpatch-through: 9.5
2018-08-25 13:35:14 -04:00
Bruce Momjian
3c712c580e doc: add doc link for 'applicable_roles'
Reported-by: Ashutosh Sharma

Discussion: https://postgr.es/m/CAE9k0PnhnL6MNDLuvkk8USzOa_DpzDzFQPAM_uaGuXbh9HMKYw@mail.gmail.com

Author: Ashutosh Sharma

Backpatch-through: 9.3
2018-08-25 13:01:24 -04:00
Bruce Momjian
04d36cf44b docs: Clarify pg_ctl initdb option text to match options proto.
The options string appeared in PG 10.

Reported-by: pgsql-kr@postgresql.kr

Discussion: https://postgr.es/m/153500377658.1378.6587007319641704057@wrigleys.postgresql.org

Backpatch-through: 10
2018-08-25 12:01:53 -04:00
Bruce Momjian
2c852e3e53 docs: clarify plpython SD and GD dictionary behavior
Reported-by: Adam Bielański

Discussion: https://postgr.es/m/153484305538.1370.7605856225879294548@wrigleys.postgresql.org

Backpatch-through: 9.3
2018-08-25 11:52:29 -04:00
Andres Freund
24f127b004 LLVMJIT: LLVMGetHostCPUFeatures now is upstream, use LLMV version if available.
Noticed thanks to buildfarm animal seawasp.

Author: Andres Freund
Backpatch: v11-, where LLVM based JIT compliation was introduced.
2018-08-24 10:21:48 -07:00
Tom Lane
7ed1db3f46 Suppress uninitialized-variable warning in new SCRAM code.
While we generally don't sweat too much about "may be used uninitialized"
warnings from older compilers, I noticed that there's a fair number of
buildfarm animals that are producing such a warning *only* for this
variable.  So it seems worth silencing.
2018-08-24 10:51:25 -04:00
Andrew Gierth
5b4555f90c Fix lexing of standard multi-character operators in edge cases.
Commits c6b3c939b (which fixed the precedence of >=, <=, <> operators)
and 865f14a2d (which added support for the standard => notation for
named arguments) created a class of lexer tokens which look like
multi-character operators but which have their own token IDs distinct
from Op. However, longest-match rules meant that following any of
these tokens with another operator character, as in (1<>-1), would
cause them to be incorrectly returned as Op.

The error here isn't immediately obvious, because the parser would
usually still find the correct operator via the Op token, but there
were more subtle problems:

1. If immediately followed by a comment or +-, >= <= <> would be given
   the old precedence of Op rather than the correct new precedence;

2. If followed by a comment, != would be returned as Op rather than as
   NOT_EQUAL, causing it not to be found at all;

3. If followed by a comment or +-, the => token for named arguments
   would be lexed as Op, causing the argument to be mis-parsed as a
   simple expression, usually causing an error.

Fix by explicitly checking for the operators in the {operator} code
block in addition to all the existing special cases there.

Backpatch to 9.5 where the problem was introduced.

Analysis and patch by me; review by Tom Lane.
Discussion: https://postgr.es/m/87va851ppl.fsf@news-spur.riddles.org.uk
2018-08-23 21:43:51 +01:00
Andrew Gierth
0b42bd459a Reduce an unnecessary O(N^3) loop in lexer.
The lexer's handling of operators contained an O(N^3) hazard when
dealing with long strings of + or - characters; it seems hard to
prevent this case from being O(N^2), but the additional N multiplier
was not needed.

Backpatch all the way since this has been there since 7.x, and it
presents at least a mild hazard in that trying to do Bind, PREPARE or
EXPLAIN on a hostile query could take excessive time (without
honouring cancels or timeouts) even if the query was never executed.
2018-08-23 21:43:51 +01:00
Tom Lane
c781a066ea In libpq, don't look up all the hostnames at once.
Historically, we looked up the target hostname in connectDBStart, so that
PQconnectPoll did not need to do DNS name resolution.  The patches that
added multiple-target-host support to libpq preserved this division of
labor; but it's really nonsensical now, because it means that if any one
of the target hosts fails to resolve in DNS, the connection fails.  That
negates the no-single-point-of-failure goal of the feature.  Additionally,
DNS lookups aren't exactly cheap, but the code did them all even if the
first connection attempt succeeds.

Hence, rearrange so that PQconnectPoll does the lookups, and only looks
up a hostname when it's time to try that host.  This does mean that
PQconnectPoll could block on a DNS lookup --- but if you wanted to avoid
that, you should be using hostaddr, as the documentation has always
specified.  It seems fairly unlikely that any applications would really
care whether the lookup occurs inside PQconnectStart or PQconnectPoll.

In addition to calling out that fact explicitly, do some other minor
wordsmithing in the docs around the multiple-target-host feature.

Since this seems like a bug in the multiple-target-host feature,
backpatch to v10 where that was introduced.  In the back branches,
avoid moving any existing fields of struct pg_conn, just in case
any third-party code is looking into that struct.

Tom Lane, reviewed by Fabien Coelho

Discussion: https://postgr.es/m/4913.1533827102@sss.pgh.pa.us
2018-08-23 16:39:37 -04:00
Peter Eisentraut
9126b4ee1c Copy-editing of pg_verify_checksums help and ref page
Reformat synopsis, put options into better order, make the desciption
line a bit shorter, and put more details into the description.
2018-08-23 20:33:39 +02:00
Peter Eisentraut
ca02434a0b PL/pgSQL: Extend test case
This test was supposed to check the interaction of INOUT and default
parameters in a procedure call, but it only checked the case where the
parameter was not supplied.  Now it also checks the case where the
parameter was supplied.  It was already working correctly, so no code
changes required.
2018-08-23 17:22:33 +02:00
Alvaro Herrera
c2b5d17718 Return type of txid_status is text, not txid_status
Thinko in commit 857ee8e39.

Discovered-by: Gianni Ciolli
2018-08-23 11:41:43 -03:00
Peter Eisentraut
17df2a8b39 doc: Clarify some wording in PL/pgSQL about transactions
Some text was still claiming that committing transactions was not
possible in PL/pgSQL.
2018-08-22 15:43:07 +02:00
Peter Eisentraut
e0dc839e72 Change PROCEDURE to FUNCTION in CREATE TRIGGER syntax
Since procedures are now a different thing from functions, change the
CREATE TRIGGER and CREATE EVENT TRIGGER syntax to use FUNCTION in the
clause that specifies the function.  PROCEDURE is still accepted for
compatibility.

pg_dump and ruleutils.c output is not changed yet, because that would
require a change in information_schema.sql and thus a catversion change.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:45:07 +02:00
Peter Eisentraut
fd4417e8ac Change PROCEDURE to FUNCTION in CREATE OPERATOR syntax
Since procedures are now a different thing from functions, change the
CREATE OPERATOR syntax to use FUNCTION in the clause that specifies the
function.  PROCEDURE is still accepted for compatibility.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:45:07 +02:00
Peter Eisentraut
b7b16605db doc: Update uses of the word "procedure"
Historically, the term procedure was used as a synonym for function in
Postgres/PostgreSQL.  Now we have procedures as separate objects from
functions, so we need to clean up the documentation to not mix those
terms.

In particular, mentions of "trigger procedures" are changed to "trigger
functions", and access method "support procedures" are changed to
"support functions".  (The latter already used FUNCTION in the SQL
syntax anyway.)  Also, the terminology in the SPI chapter has been
cleaned up.

A few tests, examples, and code comments are also adjusted to be
consistent with documentation changes, but not everything.

Reported-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Jonathan S. Katz <jonathan.katz@excoventures.com>
2018-08-22 14:45:07 +02:00
Michael Paquier
4ed59e02f5 Do not dump identity sequences with excluded parent table
This commit prevents a crash of pg_dump caused by the exclusion of a
table which has identity columns, as the table would be correctly
excluded but not its identity sequence.  In order to fix that, identity
sequences are excluded if the parent table is defined as such.  Knowing
about such sequences has no meaning without their parent table anyway.

Reported-by: Andy Abelisto
Author: David Rowley
Reviewed-by: Peter Eisentraut, Michael Paquier
Discussion: https://postgr.es/m/153479393218.1316.8472285660264976457@wrigleys.postgresql.org
Backpatch-through: 10
2018-08-22 14:22:39 +09:00
Alvaro Herrera
561a5ab751 Fix typo 2018-08-21 17:20:43 -03:00
Alvaro Herrera
5065596e51 fix typo 2018-08-21 17:04:08 -03:00
Alvaro Herrera
6918365111 Fix typo 2018-08-21 17:01:12 -03:00
Michael Paquier
3ef153c715 Fix set of NLS translation issues
While monitoring the code, a couple of issues related to string
translation has showed up:
- Some routines for auto-updatable views return an error string, which
sometimes missed the shot.  A comment regarding string translation is
added for each routine to help with future features.
- GSSAPI authentication missed two translations.
- vacuumdb handles non-translated strings.

Reported-by: Kyotaro Horiguchi
Author: Kyotaro Horiguchi
Reviewed-by: Michael Paquier, Tom Lane
Discussion: https://postgr.es/m/20180810.152131.31921918.horiguchi.kyotaro@lab.ntt.co.jp
Backpatch-through: 9.3
2018-08-21 15:17:25 +09:00
Michael Paquier
87c596cda6 Fix typo in description of enable_parallel_hash
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20180821.115841.93250330.horiguchi.kyotaro@lab.ntt.co.jp
2018-08-21 12:15:16 +09:00
Michael Paquier
9fc9933695 Clarify comment about assignment and reset of temp namespace ID in MyProc
The new wording comes from Álvaro, which I modified a bit.

Reported-by: Andres Freund, Álvaro Herrera
Author: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/20180809165047.GK13638@paquier.xyz
Backpatch-through: 11
2018-08-21 08:37:01 +09:00
Noah Misch
8fb9aa0874 MSVC: Finish clean.bat tmp_check coverage.
Use wildcards, so one can add a TAP test suite without updating this
file.  Back-patch to v11, which omitted multiple new suites.
2018-08-19 01:12:25 -07:00
Noah Misch
4cd8479369 MSVC: Remove any tmp_check directory before running a TAP test suite.
Back-patch to v11, where commit 90627cf98a
made the GNU make build system do likewise.  Without this, when a
typical PostgresNode-using test failed, subsequent runs bailed out with
a "File exists" error.
2018-08-19 01:12:25 -07:00
Peter Eisentraut
49c1a4da64 Improve error messages for CREATE OR REPLACE PROCEDURE
Change the hint to recommend DROP PROCEDURE instead of FUNCTION.  Also
make the error message when changing the return type more specific to
the case of procedures.

Reported-by: Jeremy Evans <code@jeremyevans.net>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
2018-08-18 22:05:31 +02:00
Tom Lane
d73093c4ff Ensure schema qualification in pg_restore DISABLE/ENABLE TRIGGER commands.
Previously, this code blindly followed the common coding pattern of
passing PQserverVersion(AH->connection) as the server-version parameter
of fmtQualifiedId.  That works as long as we have a connection; but in
pg_restore with text output, we don't.  Instead we got a zero from
PQserverVersion, which fmtQualifiedId interpreted as "server is too old to
have schemas", and so the name went unqualified.  That still accidentally
managed to work in many cases, which is probably why this ancient bug went
undetected for so long.  It only became obvious in the wake of the changes
to force dump/restore to execute with restricted search_path.

In HEAD/v11, let's deal with this by ripping out fmtQualifiedId's server-
version behavioral dependency, and just making it schema-qualify all the
time.  We no longer support pg_dump from servers old enough to need the
ability to omit schema name, let alone restoring to them.  (Also, the few
callers outside pg_dump already didn't work with pre-schema servers.)

In older branches, that's not an acceptable solution, so instead just
tweak the DISABLE/ENABLE TRIGGER logic to ensure it will schema-qualify
its output regardless of server version.

Per bug #15338 from Oleg somebody.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/153452458706.1316.5328079417086507743@wrigleys.postgresql.org
2018-08-17 17:12:21 -04:00
Andrew Gierth
67b161eae3 Set scan direction appropriately for SubPlans (bug #15336)
When executing a SubPlan in an expression, the EState's direction
field was left alone, resulting in an attempt to execute the subplan
backwards if it was encountered during a backwards scan of a cursor.
Also, though much less likely, it was possible to reach the execution
of an InitPlan while in backwards-scan state.

Repair by saving/restoring estate->es_direction and forcing forward
scan mode in the relevant places.

Backpatch all the way, since this has been broken since 8.3 (prior to
commit c7ff7663e, SubPlans had their own EStates rather than sharing
the parent plan's, so there was no confusion over scan direction).

Per bug #15336 reported by Vladimir Baranoff; analysis and patch by
me, review by Tom Lane.

Discussion: https://postgr.es/m/153449812167.1304.1741624125628126322@wrigleys.postgresql.org
2018-08-17 15:47:49 +01:00
Bruce Momjian
45d74631b3 pg_upgrade: issue helpful error message for use on standbys
Commit 777e6ddf17 checked for a shut down
message from a standby and allowed it to continue.  This patch reports a
helpful error message in these cases, suggesting to use rsync as
documented.

Diagnosed-by: Martín Marqués

Discussion: https://postgr.es/m/CAPdiE1xYCow-reLjrhJ9DqrMu-ppNq0ChUUEvVdxhdjGRD5_eA@mail.gmail.com

Backpatch-through: 9.3
2018-08-17 10:25:48 -04:00
Michael Paquier
b43cf1dcde Mention ownership requirements for REFRESH MATERIALIZED VIEW in docs
Author: Dian Fay
Discussion: https://postgr.es/m/745abbd2-a1a0-ead8-2cb2-768c16747d97@gmail.com
Backpatch-through: 9.3
2018-08-17 11:31:47 +09:00
Thomas Munro
dedc6a2bb1 Proof-reading for documentation.
Somebody accidentally a word.  Back-patch to 9.6.

Reported-by: Justin Pryzby
Discussion: https://postgr.es/m/20180816195431.GA23707%40telsasoft.com
2018-08-17 11:37:25 +12:00
Alvaro Herrera
6589a435d8 Fix executor prune failure when plan already pruned
In a multi-layer partitioning setup, if at plan time all the
sub-partitions are pruned but the intermediate one remains, the executor
later throws a spurious error that there's nothing to prune.  That is
correct, but there's no reason to throw an error.  Therefore, don't.

Reported-by: Andreas Seltenreich <seltenreich@gmx.de>
Author: David Rowley <david.rowley@2ndquadrant.com>
Discussion: https://postgr.es/m/87in4h98i0.fsf@ansel.ydns.eu
2018-08-16 12:49:39 -03:00
Tomas Vondra
43ba5ac6aa Close the file descriptor in ApplyLogicalMappingFile
The function was forgetting to close the file descriptor, resulting
in failures like this:

  ERROR:  53000: exceeded maxAllocatedDescs (492) while trying to open
  file "pg_logical/mappings/map-4000-4eb-1_60DE1E08-5376b5-537c6b"
  LOCATION:  OpenTransientFile, fd.c:2161

Simply close the file at the end, and backpatch to 9.4 (where logical
decoding was introduced). While at it, fix a nearby typo.

Discussion: https://www.postgresql.org/message-id/flat/738a590a-2ce5-9394-2bef-7b1caad89b37%402ndquadrant.com
2018-08-16 16:55:34 +02:00
Tom Lane
36147ec9f1 Make snprintf.c follow the C99 standard for snprintf's result value.
C99 says that the result should be the number of bytes that would have
been emitted given a large enough buffer, not the number we actually
were able to put in the buffer.  It's time to make our substitute
implementation comply with that.  Not doing so results in inefficiency
in buffer-enlargement cases, and also poses a portability hazard for
third-party code that might expect C99-compliant snprintf behavior
within Postgres.

In passing, remove useless tests for str == NULL; neither C99 nor
predecessor standards ever allowed that except when count == 0,
so I see no reason to expend cycles on making that a non-crash case
for this implementation.  Also, don't waste a byte in pg_vfprintf's
local I/O buffer; this might have performance benefits by allowing
aligned writes during flushbuffer calls.

Back-patch of commit 805889d7d.  There was some concern about this
possibly breaking code that assumes pre-C99 behavior, but there is
much more risk (and reality, in our own code) of code that assumes
C99 behavior and hence fails to detect buffer overrun without this.

Discussion: https://postgr.es/m/17245.1534289329@sss.pgh.pa.us
2018-08-15 17:25:49 -04:00
Alvaro Herrera
6872c2be6a Update FSM on WAL replay of page all-visible/frozen
We aren't very strict about keeping FSM up to date on WAL replay,
because per-page freespace values aren't critical in replicas (can't
write to heap in a replica; and if the replica is promoted, the values
would be updated by VACUUM anyway).  However, VACUUM since 9.6 can skip
processing pages marked all-visible or all-frozen, and if such pages are
recorded in FSM with wrong values, those values are blindly propagated
to FSM's upper layers by VACUUM's FreeSpaceMapVacuum.  (This rationale
assumes that crashes are not very frequent, because those would cause
outdated FSM to occur in the primary.)

Even when the FSM is outdated in standby, things are not too bad
normally, because, most per-page FSM values will be zero (other than
those propagated with the base-backup that created the standby); only
once the remaining free space is less than 0.2*BLCKSZ the per-page value
is maintained by WAL replay of heap ins/upd/del.  However, if
wal_log_hints=on causes complete FSM pages to be propagated to a standby
via full-page images, many too-optimistic per-page values can end up
being registered in the standby.

Incorrect per-page values aren't critical in most cases, since an
inserter that is given a page that doesn't actually contain the claimed
free space will update FSM with the correct value, and retry until it
finds a usable page.  However, if there are many such updates to do, an
inserter can spend a long time doing them before a usable page is found;
in a heavily trafficked insert-only table with many concurrent inserters
this has been observed to cause several second stalls, causing visible
application malfunction.

To fix this problem, it seems sufficient to have heap_xlog_visible
(replay of setting all-visible and all-frozen VM bits for a heap page)
update the FSM value for the page being processed.  This fixes the
per-page counters together with making the page skippable to vacuum, so
when vacuum does FreeSpaceMapVacuum, the values propagated to FSM upper
layers are the correct ones, avoiding the problem.

While at it, apply the same fix to heap_xlog_clean (replay of tuple
removal by HOT pruning and vacuum).  This makes any space freed by the
cleaning available earlier than the next vacuum in the promoted replica.

Backpatch to 9.6, where this problem was diagnosed on an insert-only
table with all-frozen pages, which were introduced as a concept in that
release.  Theoretically it could apply with all-visible pages to older
branches, but there's been no report of that and it doesn't backpatch
cleanly anyway.

Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20180802172857.5skoexsilnjvgruk@alvherre.pgsql
2018-08-15 18:09:29 -03:00
Tom Lane
d7ed4eea53 Clean up assorted misuses of snprintf()'s result value.
Fix a small number of places that were testing the result of snprintf()
but doing so incorrectly.  The right test for buffer overrun, per C99,
is "result >= bufsize" not "result > bufsize".  Some places were also
checking for failure with "result == -1", but the standard only says
that a negative value is delivered on failure.

(Note that this only makes these places correct if snprintf() delivers
C99-compliant results.  But at least now these places are consistent
with all the other places where we assume that.)

Also, make psql_start_test() and isolation_start_test() check for
buffer overrun while constructing their shell commands.  There seems
like a higher risk of overrun, with more severe consequences, here
than there is for the individual file paths that are made elsewhere
in the same functions, so this seemed like a worthwhile change.

Also fix guc.c's do_serialize() to initialize errno = 0 before
calling vsnprintf.  In principle, this should be unnecessary because
vsnprintf should have set errno if it returns a failure indication ...
but the other two places this coding pattern is cribbed from don't
assume that, so let's be consistent.

These errors are all very old, so back-patch as appropriate.  I think
that only the shell command overrun cases are even theoretically
reachable in practice, but there's not much point in erroneous error
checks.

Discussion: https://postgr.es/m/17245.1534289329@sss.pgh.pa.us
2018-08-15 16:29:32 -04:00
Bruce Momjian
995133410d pg_upgrade: fix shutdown check for standby servers
Commit 244142d32a only tested for the
pg_controldata output for primary servers, but standby servers have
different "Database cluster state" output, so check for that too.

Diagnosed-by: Michael Paquier

Discussion: https://postgr.es/m/20180810164240.GM13638@paquier.xyz

Backpatch-through: 9.3
2018-08-14 17:19:02 -04:00
Peter Eisentraut
c6eedb4d86 doc: Update broken links
Discussion: https://www.postgresql.org/message-id/flat/153044458767.13254.16049977382403131287%40wrigleys.postgresql.org
2018-08-14 22:56:07 +02:00
Tom Lane
d39079a8b2 Remove duplicate function declarations.
Christoph Berg

Discussion: https://postgr.es/m/20180814165536.GB21152@msg.df7cb.de
2018-08-14 14:25:14 -04:00
Peter Eisentraut
4c9611e576 Remove obsolete comment
The sequence name is no longer stored in the sequence relation, since
1753b1b027.
2018-08-13 21:08:01 +02:00
Tom Lane
998c736641 Fix libpq's implementation of per-host connection timeouts.
Commit 5f374fe7a attempted to turn the connect_timeout from an overall
maximum time limit into a per-host limit, but it didn't do a great job of
that.  The timer would only get restarted if we actually detected timeout
within connectDBComplete(), not if we changed our attention to a new host
for some other reason.  In that case the old timeout continued to run,
possibly causing a premature timeout failure for the new host.

Fix that, and also tweak the logic so that if we do get a timeout,
we advance to the next available IP address, not to the next host name.
There doesn't seem to be a good reason to assume that all the IP
addresses supplied for a given host name will necessarily fail the
same way as the current one.  Moreover, this conforms better to the
admittedly-vague documentation statement that the timeout is "per
connection attempt".  I changed that to "per host name or IP address"
to be clearer.  (Note that reconnections to the same server, such as for
switching protocol version or SSL status, don't get their own separate
timeout; that was true before and remains so.)

Also clarify documentation about the interpretation of connect_timeout
values less than 2.

This seems like a bug, so back-patch to v10 where this logic came in.

Tom Lane, reviewed by Fabien Coelho

Discussion: https://postgr.es/m/5735.1533828184@sss.pgh.pa.us
2018-08-13 13:07:52 -04:00
Michael Paquier
943576bddc Make autovacuum more aggressive to remove orphaned temp tables
Commit dafa084, added in 10, made the removal of temporary orphaned
tables more aggressive.  This commit makes an extra step into the
aggressiveness by adding a flag in each backend's MyProc which tracks
down any temporary namespace currently in use.  The flag is set when the
namespace gets created and can be reset if the temporary namespace has
been created in a transaction or sub-transaction which is aborted.  The
flag value assignment is assumed to be atomic, so this can be done in a
lock-less fashion like other flags already present in PGPROC like
databaseId or backendId, still the fact that the temporary namespace and
table created are still locked until the transaction creating those
commits acts as a barrier for other backends.

This new flag gets used by autovacuum to discard more aggressively
orphaned tables by additionally checking for the database a backend is
connected to as well as its temporary namespace in-use, removing
orphaned temporary relations even if a backend reuses the same slot as
one which created temporary relations in a past session.

The base idea of this patch comes from Robert Haas, has been written in
its first version by Tsunakawa Takayuki, then heavily reviewed by me.

Author: Tsunakawa Takayuki
Reviewed-by: Michael Paquier, Kyotaro Horiguchi, Andres Freund
Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F8A4DC6@G01JPEXMBYT05
Backpatch: 11-, as PGPROC gains a new flag and we don't want silent ABI
breakages on already released versions.
2018-08-13 11:49:12 +02:00