Commit Graph

47720 Commits

Author SHA1 Message Date
Alexander Korotkov 02f90879e7 Fix handling of NULL distances in KNN-GiST
In order to implement NULL LAST semantic GiST previously assumed distance to
the NULL value to be Inf.  However, our distance functions can return Inf and
NaN for non-null values.  In such cases, NULL LAST semantic appears to be
broken.  This commit fixes that by introducing separate array of null flags for
distances.

Backpatch to all supported versions.

Discussion: https://postgr.es/m/CAPpHfdsNvNdA0DBS%2BwMpFrgwT6C3-q50sFVGLSiuWnV3FqOJuQ%40mail.gmail.com
Author: Alexander Korotkov
Backpatch-through: 9.4
2019-09-08 22:08:12 +03:00
Alexander Korotkov e5d8f35961 Fix handling Inf and Nan values in GiST pairing heap comparator
Previously plain float comparison was used in GiST pairing heap.  Such
comparison doesn't provide proper ordering for value sets containing Inf and Nan
values.  This commit fixes that by usage of float8_cmp_internal().  Note, there
is remaining problem with NULL distances, which are represented as Inf in
pairing heap.  It would be fixes in subsequent commit.

Backpatch to all supported versions.

Reported-by: Andrey Borodin
Discussion: https://postgr.es/m/CAPpHfdsNvNdA0DBS%2BwMpFrgwT6C3-q50sFVGLSiuWnV3FqOJuQ%40mail.gmail.com
Author: Alexander Korotkov
Reviewed-by: Heikki Linnakangas
Backpatch-through: 9.4
2019-09-08 22:08:12 +03:00
Peter Eisentraut 862ef372d6 Fix behavior of AND CHAIN outside of explicit transaction blocks
When using COMMIT AND CHAIN or ROLLBACK AND CHAIN not in an explicit
transaction block, the previous implementation would leave a
transaction block active in the ROLLBACK case but not the COMMIT case.
To fix for now, error out when using these commands not in an explicit
transaction block.  This restriction could be lifted if a sensible
definition and implementation is found.

Bug: #15977
Author: fn ln <emuser20140816@gmail.com>
Reviewed-by: Fabien COELHO <coelho@cri.ensmp.fr>
2019-09-08 16:23:03 +02:00
Peter Eisentraut 0e77746212 doc: effective -> efficient 2019-09-08 11:10:49 +02:00
Peter Eisentraut 8e929a4667 doc: Clean up title case use
Note: Following existing practice, titles of formalpara and step are
not titlecased.
2019-09-08 10:27:29 +02:00
Tom Lane db43831899 Avoid using INFO elevel for what are fundamentally debug messages.
Commit 6f6b99d13 stuck an INFO message into the fast path for
checking partition constraints, for no very good reason except
that it made it easy for the regression tests to verify that
that path was taken.  Assorted later patches did likewise,
increasing the unsuppressable-chatter level from ALTER TABLE
even more.  This isn't good for the user experience, so let's
drop these messages down to DEBUG1 where they belong.  So as
not to have a loss of test coverage, create a TAP test that
runs the relevant queries with client_min_messages = DEBUG1
and greps for the expected messages.

This testing method is a bit brute-force --- in particular,
it duplicates the execution of a fair amount of the core
create_table and alter_table tests.  We experimented with
other solutions, but running any significant amount of
standard testing with client_min_messages = DEBUG1 seems
to have a lot of output-stability pitfalls, cf commits
bbb96c370 and 5655565c0.  Possibly at some point we'll look
into whether we can reduce the amount of test duplication.

Backpatch into v12, because some of these messages are new
in v12 and we don't really want to ship it that way.

Sergei Kornilov

Discussion: https://postgr.es/m/81911511895540@web58j.yandex.ru
Discussion: https://postgr.es/m/4859321552643736@myt5-02b80404fd9e.qloud-c.yandex.net
2019-09-07 19:03:11 -04:00
Tom Lane ca70bdaefe Fix issues around strictness of SIMILAR TO.
As a result of some long-ago quick hacks, the SIMILAR TO operator
and the corresponding flavor of substring() interpreted "ESCAPE NULL"
as selecting the default escape character '\'.  This is both
surprising and not per spec: the standard is clear that these
functions should return NULL for NULL input.

Additionally, because of inconsistency of the strictness markings
of 3-argument substring() and similar_escape(), the planner could not
inline the SQL definition of substring(), resulting in a substantial
performance penalty compared to the underlying POSIX substring()
function.

The simplest fix for this would be to change the strictness marking
of similar_escape(), but if we do that we risk breaking existing views
that depend on that function.  Hence, leave similar_escape() as-is
as a compatibility function, and instead invent a new function
similar_to_escape() that comes in two strict variants.

There are a couple of other behaviors in this area that are also
not per spec, but they are documented and seem generally at least
as sane as the spec's definition, so leave them alone.  But improve
the documentation to describe them fully.

Patch by me; thanks to Álvaro Herrera and Andrew Gierth for review
and discussion.

Discussion: https://postgr.es/m/14047.1557708214@sss.pgh.pa.us
2019-09-07 14:21:59 -04:00
Peter Eisentraut c5bc7050af Message style fixes 2019-09-06 22:54:02 +02:00
Peter Eisentraut 021da890bc doc: Fix awkward markup 2019-09-06 22:19:53 +02:00
Peter Eisentraut c57dbc1989 doc: Postgres -> PostgreSQL 2019-09-06 22:16:58 +02:00
Andrew Dunstan 8e5ce1c3f8 Always skip recovery SysV shared memory tests on Windows
The test for SysV support currently involves looking for the perl
modules IPC::SharedMem and IPC::SysV. However, the perl on msys2 has
these modules but the tests fail. Therefore, force skipping the tests on
Windows platforms unconditionally.

Discussion: https://postgr.es/m/176e86ba-1a46-9d8c-5ae4-9865a463b411@2ndQuadrant.com
2019-09-06 15:50:53 -04:00
Tom Lane 71a0108660 Doc: tweak installation doc edits made by commit 76c2af926.
We don't consider that building with MinGW is deprecated,
so adjust some places that gave that impression.
Per discussion with Peter Eisentraut.

Discussion: https://postgr.es/m/4a023388-8652-fea0-a0b4-35ad5e734e9a@2ndquadrant.com
2019-09-06 11:24:42 -04:00
Robert Haas bd124996ef Create an API for inserting and deleting rows in TOAST tables.
This moves much of the non-heap-specific logic from toast_delete and
toast_insert_or_update into a helper functions accessible via a new
header, toast_helper.h.  Using the functions in this module, a table
AM can implement creation and deletion of TOAST table rows with
much less code duplication than was possible heretofore.  Some
table AMs won't want to use the TOAST logic at all, but for those
that do this will make that easier.

Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro,
Andres Freund, and Álvaro Herrera.

Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
2019-09-06 10:38:51 -04:00
Robert Haas 286af0ce12 When performing a base backup, check for read errors.
The old code didn't differentiate between a read error and a
concurrent truncation. fread reports both of these by returning 0;
you have to use feof() or ferror() to distinguish between them,
which this code did not do.

It might be a better idea to use read() rather than fread() here,
so that we can display a less-generic error message, but I'm not
sure that would qualify as a back-patchable bug fix, so just do
this much for now.

Jeevan Chalke, reviewed by Jeevan Ladhe and by me.

Discussion: http://postgr.es/m/CA+TgmobG4ywMzL5oQq2a8YKp8x2p3p1LOMMcGqpS7aekT9+ETA@mail.gmail.com
2019-09-06 08:22:32 -04:00
Peter Eisentraut 5599f40d25 libpq: ccache -> credential cache
The term "ccache" is overloaded.  Let's be more clear, in case someone
other than a Kerberos wizard has to read this code.
2019-09-06 09:15:35 +02:00
Fujii Masao 946647f845 Make pg_promote() detect postmaster death while waiting for promotion to end.
Previously even if postmaster died and WaitLatch() woke up with that event
while pg_promote() was waiting for the standby promotion to finish,
pg_promote() did nothing special and kept waiting until timeout occurred.
This could cause a busy loop.

This patch make pg_promote() return false immediately when postmaster
dies, to avoid such a busy loop.

Back-patch to v12 where pg_promote() was added.

Author: Fujii Masao
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAHGQGwEs9ROgSp+QF+YdDU+xP8W=CY1k-_Ov-d_Z3JY+to3eXA@mail.gmail.com
2019-09-06 14:27:25 +09:00
Michael Paquier fc8cb94bf4 Make use of generic logging in vacuumlo and oid2name
Doing the switch reduces the footprint of "progname" in both utilities
for the messages produced.  This also cleans up a couple of
inconsistencies in the message formats.

Author: Michael Paquier
Reviewed-by: Álvaro Herrera, Peter Eisentraut
Discussion: https://postgr.es/m/20190820012819.GA8326@paquier.xyz
2019-09-06 14:00:13 +09:00
Tom Lane 7de19fbc0b Use data directory inode number, not port, to select SysV resource keys.
This approach provides a much tighter binding between a data directory
and the associated SysV shared memory block (and SysV or named-POSIX
semaphores, if we're using those).  Key collisions are still possible,
but only between data directories stored on different filesystems,
so the situation should be negligible in practice.  More importantly,
restarting the postmaster with a different port number no longer
risks failing to identify a relevant shared memory block, even when
postmaster.pid has been removed.  A standalone backend is likewise
much more certain to detect conflicting leftover backends.

(In the longer term, we might now think about deprecating the port as
a cluster-wide value, so that one postmaster could support sockets
with varying port numbers.  But that's for another day.)

The hazards fixed here apply only on Unix systems; our Windows code
paths already use identifiers derived from the data directory path
name rather than the port.

src/test/recovery/t/017_shm.pl, which intends to test key-collision
cases, has been substantially rewritten since it can no longer use
two postmasters with identical port numbers to trigger the case.
Instead, use Perl's IPC::SharedMem module to create a conflicting
shmem segment directly.  The test script will be skipped if that
module is not available.  (This means that some older buildfarm
members won't run it, but I don't think that that results in any
meaningful coverage loss.)

Patch by me; thanks to Noah Misch and Peter Eisentraut for discussion
and review.

Discussion: https://postgr.es/m/16908.1557521200@sss.pgh.pa.us
2019-09-05 13:31:46 -04:00
Robert Haas 8b94dab066 Split tuptoaster.c into three separate files.
detoast.c/h contain functions required to detoast a datum, partially
or completely, plus a few other utility functions for examining the
size of toasted datums.

toast_internals.c/h contain functions that are used internally to the
TOAST subsystem but which (mostly) do not need to be accessed from
outside.

heaptoast.c/h contains code that is intrinsically specific to the
heap AM, either because it operates on HeapTuples or is based on the
layout of a heap page.

detoast.c and toast_internals.c are placed in
src/backend/access/common rather than src/backend/access/heap.  At
present, both files still have dependencies on the heap, but that will
be improved in a future commit.

Patch by me, reviewed and tested by Prabhat Sabu, Thomas Munro,
Andres Freund, and Álvaro Herrera.

Discussion: http://postgr.es/m/CA+TgmoZv-=2iWM4jcw5ZhJeL18HF96+W1yJeYrnGMYdkFFnEpQ@mail.gmail.com
2019-09-05 13:15:10 -04:00
Peter Eisentraut 74a308cf52 Use explicit_bzero
Use the explicit_bzero() function in places where it is important that
security information such as passwords is cleared from memory.  There
might be other places where it could be useful; this is just an
initial collection.

For platforms that don't have explicit_bzero(), provide various
fallback implementations.  (explicit_bzero() itself isn't standard,
but as Linux/glibc, FreeBSD, and OpenBSD have it, it's the most common
spelling, so it makes sense to make that the invocation point.)

Discussion: https://www.postgresql.org/message-id/flat/42d26bde-5d5b-c90d-87ae-6cab875f73be%402ndquadrant.com
2019-09-05 08:30:42 +02:00
Michael Paquier ae060a52b2 Fix thinko when ending progress report for a backend
The logic ending progress reporting for a backend entry introduced by
b6fb647 causes callers of pgstat_progress_end_command() to do some extra
work when track_activities is enabled as the process fields are reset in
the backend entry even if no command were started for reporting.

This resets the fields only if a command is registered for progress
reporting, and only if track_activities is enabled.

Author: Masahiho Sawada
Discussion: https://postgr.es/m/CAD21AoCry_vJ0E-m5oxJXGL3pnos-xYGCzF95rK5Bbi3Uf-rpA@mail.gmail.com
Backpatch-through: 9.6
2019-09-04 15:46:37 +09:00
Michael Paquier 522baf1484 Delay fsyncs of pg_basebackup until the end of backup
Since the addition of fsync requests in bc34223 to make base backup data
consistent on disk once pg_basebackup finishes, each tablespace tar file
is individually flushed once completed, with an additional flush of the
parent directory when the base backup finishes.  While holding a
connection to the server, a fsync request taking a long time may cause a
failure of the base backup, which is annoying for any integration.  A
recent example of breakage can involve tcp_user_timeout, but
wal_sender_timeout can cause similar problems.

While reviewing the code, there was a second issue causing too many
fsync requests to be done for the same WAL data.  As recursive fsyncs
are done at the end of the backup for both the plain and tar formats
from the base target directory where everything is written, it is fine
to disable fsyncs when fetching or streaming WAL.

Reported-by: Ryohei Takahashi
Author: Michael Paquier
Reviewed-by: Ryohei Takahashi
Discussion: https://postgr.es/m/OSBPR01MB4550DAE2F8C9502894A45AAB82BE0@OSBPR01MB4550.jpnprd01.prod.outlook.com
Backpatch-through: 10
2019-09-04 13:21:11 +09:00
Alvaro Herrera 25dcc9d35d Make XLogReaderInvalReadState static
This function is only used by xlogreader.c itself, so there's no need to
export it.  It was introduced by commit 3b02ea4f07 with the apparent
intention that it could be used externally, but I couldn't find any
external code calling it.

I (Álvaro) couldn't resist the urge to sort nearby function prototypes
properly while at it.

Author: Antonin Houska
Discussion: https://postgr.es/m/14984.1554998742@spoje.net
2019-09-03 17:41:43 -04:00
Alvaro Herrera fe66125974 Remove 'msg' parameter from convert_tuples_by_name
The message was included as a parameter when this function was added in
dcb2bda9b7, but I don't think it has ever served any useful purpose.
Let's stop spreading it pointlessly.

Reviewed by Amit Langote and Peter Eisentraut.

Discussion: https://postgr.es/m/20190806224728.GA17233@alvherre.pgsql
2019-09-03 14:47:29 -04:00
Peter Eisentraut 10f5544896 Clarify pg_dump documentation
Clarify in the help output and documentation that -n, -t etc. take a
"pattern" rather than a "schema" or "table" etc.  This was especially
confusing now that the new pg_dumpall --exclude-database option was
documented with "pattern" and the others not, even though they all
behave the same.

Discussion: https://www.postgresql.org/message-id/flat/b85f3fa1-b350-38d1-1893-4f7911bd7310%402ndquadrant.com
2019-09-03 14:25:26 +02:00
Peter Eisentraut bde8c2d319 Improve base backup protocol documentation
Document that the tablespace sizes are in units of kilobytes.  Make
the pg_basebackup source code a bit clearer about this, too.

Reviewed-by: Magnus Hagander <magnus@hagander.net>
2019-09-03 11:59:36 +02:00
Peter Eisentraut 1d7a6e3eb4 pg_checksums: Handle read and write returns correctly
The read() return was not checking for errors, the write() return was
not checking for short writes.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/5de61b6b-8be9-7771-0048-860328efe027%402ndquadrant.com
2019-09-03 08:30:21 +02:00
Peter Eisentraut 396e4afdbc Better error messages for short reads/writes in SLRU
This avoids getting a

    Could not read from file ...: Success.

for a short read or write (since errno is not set in that case).
Instead, report a more specific error messages.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/5de61b6b-8be9-7771-0048-860328efe027%402ndquadrant.com
2019-09-03 08:30:21 +02:00
Michael Paquier 4e72a8e11e Doc: Replace mention to "K bytes" by "kilobytes" in textsearch.sgml
"kB" or "kilobyte" is used in the documentation.

Author: Daniel Gustafsson
Discussion: https://postgr.es/m/32BA3AF7-37E9-4334-A226-98B844ADCC4E@yesql.se
2019-09-03 13:03:29 +09:00
Michael Paquier 3a54eb1a38 Fix memory leak with lower, upper and initcap with ICU-provided collations
The leak happens in str_tolower, str_toupper and str_initcap, which are
used in several places including their equivalent SQL-level functions,
and can only be triggered when using an ICU-provided collation when
converting the input string.

b615920 fixed a similar leak.  Backpatch down 10 where ICU collations
have been introduced.

Author: Konstantin Knizhnik
Discussion: https://postgr.es/m/94c0ad0a-cbc2-e4a3-7829-2bdeaf9146db@postgrespro.ru
Backpatch-through: 10
2019-09-03 12:30:53 +09:00
Tom Lane f63a5ead9d Avoid touching replica identity index in ExtractReplicaIdentity().
In what seems like a fit of misplaced optimization,
ExtractReplicaIdentity() accessed the relation's replica-identity
index without taking any lock on it.  Usually, the surrounding query
already holds some lock so this is safe enough ... but in the case
of a previously-planned delete, there might be no existing lock.
Given a suitable test case, this is exposed in v12 and HEAD by an
assertion added by commit b04aeb0a0.

The whole thing's rather poorly thought out anyway; rather than
looking directly at the index, we should use the index-attributes
bitmap that's held by the parent table's relcache entry, as the
caller functions do.  This is more consistent and likely a bit
faster, since it avoids a cache lookup.  Hence, change to doing it
that way.

While at it, rather than blithely assuming that the identity
columns are non-null (with catastrophic results if that's wrong),
add assertion checks that they aren't null.  Possibly those should
be actual test-and-elog, but I'll leave it like this for now.

In principle, this is a bug that's been there since this code was
introduced (in 9.4).  In practice, the risk seems quite low, since
we do have a lock on the index's parent table, so concurrent
changes to the index's catalog entries seem unlikely.  Given the
precedent that commit 9c703c169 wasn't back-patched, I won't risk
back-patching this further than v12.

Per report from Hadi Moshayedi.

Discussion: https://postgr.es/m/CAK=1=Wrek44Ese1V7LjKiQS-Nd-5LgLi_5_CskGbpggKEf3tKQ@mail.gmail.com
2019-09-02 16:10:37 -04:00
Tom Lane aef3623858 Handle corner cases correctly in psql's reconnection logic.
After an unexpected connection loss and successful reconnection,
psql neglected to resynchronize its internal state about the server,
such as server version.  Ordinarily we'd be reconnecting to the same
server and so this isn't really necessary, but there are scenarios
where we do need to update --- one example is where we have a list
of possible connection targets and they're not all alike.

Define "resynchronize" as including connection_warnings(), so that
this case acts the same as \connect.  This seems useful; for example,
if the server version did change, the user might wish to know that.
An attuned user might also notice that the new connection isn't
SSL-encrypted, for example, though this approach isn't especially
in-your-face about such changes.  Although this part is a behavioral
change, it only affects interactive sessions, so it should not break
any applications.

Also, in do_connect, make sure that we desynchronize correctly when
abandoning an old connection in non-interactive mode.

These problems evidently are the result of people patching only one
of the two places where psql deals with connection changes, so insert
some cross-referencing comments in hopes of forestalling future bugs
of the same ilk.

Lastly, in Windows builds, issue codepage mismatch warnings only at
startup, not during reconnections.  psql's codepage can't change
during a reconnect, so complaining about it again seems like useless
noise.

Peter Billen and Tom Lane.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAMTXbE8e6U=EBQfNSe01Ej17CBStGiudMAGSOPaw-ALxM-5jXg@mail.gmail.com
2019-09-02 14:03:05 -04:00
Alvaro Herrera 6fcc40b1d4 Add POD documentation to TestLib.pm
This module was pretty much undocumented.  Fix that.

Inspired by a preliminary patch sent by Ramanarayana, heavily updated by
Andrew Dunstan, and reviewed by Michael Paquier.

Discussion: https://postgr.es/m/CAF6A77G_WJTwBV9SBxCnQfZB09hm1p1O3stZ6eE5QiYd=X84Jg@mail.gmail.com
2019-09-02 13:37:57 -04:00
Michael Paquier 7dedfd22b7 Add overflow-safe math inline functions for unsigned integers
Similarly to the signed versions added in 4d6ad31, this adds a set of
inline functions for overflow checks with unsigned integers, including
uint16, uint32 and uint64.  This relies on compiler built-in overflow
checks by default if available.  The behavior of unsigned integers is
well-defined so the fallback implementations checks are simple for
additions and subtractions.  Multiplications avoid division-based checks
which are expensive if possible, still this can happen for uint64 if
128-bit integers are not available.

While on it, the code in common/int.h is reorganized to avoid too many
duplicated comments.  The new macros will be used in a follow-up patch.

All thanks to Andres Freund for the input provided.

Author: Fabien Coelho, Michael Paquier
Discussion: https://postgr.es/m/20190830073423.GB2354@paquier.xyz
2019-09-02 09:38:23 +09:00
Peter Eisentraut 36515e4f14 Fix compiler warning
Fix a warning about unused variable on Windows when using OpenSSL.
2019-09-01 23:19:51 +02:00
Tom Lane 756349c87b Doc: describe the "options" allowed in an ECPG connection target string.
These have been there a long time, but their format was never explained
in the docs.  Per complaint from Yusuke Egashira.

Discussion: https://postgr.es/m/848B1649C8A6274AA527C4472CA11EDD5FC70CBE@G01JPEXMBYT02
2019-08-31 14:05:32 -04:00
Tom Lane b61a5e6a1f Cosmetic improvements for options-handling code in ECPGconnect().
The comment describing the string format was a lie.  Make it agree with
reality, add/improve some other comments, fix coding style for loops with
empty bodies.  Also add an Assert that we counted parameters correctly,
because the spread-out logic for that looks pretty fragile.

No actual bugs fixed here, so no need to back-patch.

Discussion: https://postgr.es/m/848B1649C8A6274AA527C4472CA11EDD5FC70CBE@G01JPEXMBYT02
2019-08-31 13:37:10 -04:00
Tom Lane 137b03b862 Doc: restructure documentation of the configure script's options.
The list of configure options has grown long, and there was next
to no organization to it, never mind any indication of which options
were interesting to most people.  Break it into several sub-sections
to provide a bit of structure, and add some introductory text where
it seems helpful to point people to particular options.

I failed to resist the temptation to do a small amount of
word-smithing on some of the option descriptions, too.
But mostly this is reorganization and addition of intro text.

Discussion: https://postgr.es/m/6384.1559917369@sss.pgh.pa.us
2019-08-30 15:44:00 -04:00
Tom Lane 76c2af9266 Doc: remove some long-obsolete information from installation.sgml.
Section 16.2 pointed to platform-specific FAQ files that we removed
way back in 8.4.  Section 16.7 contained a bunch of information about
AIX and HPUX bugs that were squashed decades ago, plus discussions of
old compiler versions that are certainly moot now that we require C99
support.  Since we're obviously not maintaining this stuff carefully,
just remove it.  The HPUX sub-section seems like it can go away
entirely, since everything it said that was still applicable was
redundant with material elsewhere in the chapter.

In passing, I couldn't resist the temptation to do a small amount
of copy-editing on nearby text.

Back-patch to v12, since this stuff is surely obsolete in any
branch that requires C99.

Discussion: https://postgr.es/m/15538.1567042743@sss.pgh.pa.us
2019-08-30 13:02:35 -04:00
Peter Eisentraut 9684e42695 Error out on too many command-line arguments
Fix up oid2name, pg_upgrade, and pgbench to error out on too many
command-line arguments.  This makes it match the behavior of other
PostgreSQL programs.

Author: Peter Eisentraut, Ibrar Ahmed
Discussion: https://www.postgresql.org/message-id/flat/f2554627-04e7-383a-ef01-ab99bb6a291c%402ndquadrant.com
2019-08-29 18:49:41 +02:00
Etsuro Fujita 317b3d7ae2 Fix typos in regression test comments. 2019-08-29 18:45:00 +09:00
Tom Lane 744c848dce Add .gitignore file forgotten in commit bde7493d1. 2019-08-28 12:59:47 -04:00
Heikki Linnakangas bde7493d10 Fix overflow check and comment in GIN posting list encoding.
The comment did not match what the code actually did for integers with
the 43rd bit set. You get an integer like that, if you have a posting
list with two adjacent TIDs that are more than 2^31 blocks apart.
According to the comment, we would store that in 6 bytes, with no
continuation bit on the 6th byte, but in reality, the code encodes it
using 7 bytes, with a continuation bit on the 6th byte as normal.

The decoding routine also handled these 7-byte integers correctly, except
for an overflow check that assumed that one integer needs at most 6 bytes.
Fix the overflow check, and fix the comment to match what the code
actually does. Also fix the comment that claimed that there are 17 unused
bits in the 64-bit representation of an item pointer. In reality, there
are 64-32-11=21.

Fitting any item pointer into max 6 bytes was an important property when
this was written, because in the old pre-9.4 format, item pointers were
stored as plain arrays, with 6 bytes for every item pointer. The maximum
of 6 bytes per integer in the new format guaranteed that we could convert
any page from the old format to the new format after upgrade, so that the
new format was never larger than the old format. But we hardly need to
worry about that anymore, and running into that problem during upgrade,
where an item pointer is expanded from 6 to 7 bytes such that the data
doesn't fit on a page anymore, is implausible in practice anyway.

Backpatch to all supported versions.

This also includes a little test module to test these large distances
between item pointers, without requiring a 16 TB table. It is not
backpatched, I'm including it more for the benefit of future development
of new posting list formats.

Discussion: https://www.postgresql.org/message-id/33bfc20a-5c86-f50c-f5a5-58e9925d05ff%40iki.fi
Reviewed-by: Masahiko Sawada, Alexander Korotkov
2019-08-28 12:55:33 +03:00
Thomas Munro 720b59b55b Avoid catalog lookups in RelationAllowsEarlyPruning().
RelationAllowsEarlyPruning() performed a catalog scan, but is used
in two contexts where that was a bad idea:

1.  In heap_page_prune_opt(), which runs very frequently in some large
    scans.  This caused major performance problems in a field report
    that was easy to reproduce.

2.  In TestForOldSnapshot(), which runs while we hold a buffer content
    lock.  It's not clear if this was guaranteed to be free of buffer
    deadlock risk.

The check was introduced in commit 2cc41acd8 and defended against a
real problem: 9.6's hash indexes have no page LSN and so we can't
allow early pruning (ie the snapshot-too-old feature).  We can remove
the check from all later releases though: hash indexes are now logged,
and there is no way to create UNLOGGED indexes on regular logged
tables.

If a future release allows such a combination, it might need to put
a similar check in place, but it'll need some more thought.

Back-patch to 10.

Author: Thomas Munro
Reviewed-by: Tom Lane, who spotted the second problem
Discussion: https://postgr.es/m/CA%2BhUKGKT8oTkp5jw_U4p0S-7UG9zsvtw_M47Y285bER6a2gD%2Bg%40mail.gmail.com
Discussion: https://postgr.es/m/CAA4eK1%2BWy%2BN4eE5zPm765h68LrkWc3Biu_8rzzi%2BOYX4j%2BiHRw%40mail.gmail.com
2019-08-28 16:18:29 +12:00
Michael Paquier 80d0e5ba3f Improve coverage of utils/float.h
check_float4_val() checks after underflow and overflow of values
converted from float8 to float4, but there has never been any regression
tests for that.  This brings the coverage of float.h to 100%.

Author: Movead Li
Discussion: https://postgr.es/m/20190822174636998766188@highgo.ca
2019-08-28 12:28:16 +09:00
Michael Paquier be182e4f9e Disable timeouts when running pg_rewind with online source cluster
In this case, the transfer uses a libpq connection, which is subject to
the timeout parameters set at system level, and this can make the rewind
operation suddenly canceled which is not good for automation.  One
workaround to such issues would be to use PGOPTIONS to enforce the
wanted timeout parameters, but that's annoying, and for example pg_dump,
which can run potentially long-running queries disables all types of
timeouts.

lock_timeout and statement_timeout are the ones which can cause problems
now.  Note that pg_rewind does not use transactions, so disabling
idle_in_transaction_session_timeout is optional, but it feels safer to
do so for the future.

This is back-patched down to 9.5.  idle_in_transaction_session_timeout
is only present since 9.6.

Author: Alexander Kukushkin
Discussion: https://postgr.es/m/CAFh8B=krcVXksxiwVQh1SoY+ziJ-JC=6FcuoBL3yce_40Es5_g@mail.gmail.com
Backpatch-through: 9.5
2019-08-28 11:47:35 +09:00
Tom Lane b1907d6882 Set application_name per-test in isolation and ecpg tests.
Commit a4327296d taught pg_regress proper to do this, but
missed the opportunity to do likewise in the isolationtester
and ecpg variants of pg_regress.  Seems like this might be
helpful for tracking down issues exposed by those tests.
2019-08-27 19:49:09 -04:00
Tom Lane 458f01e254 Doc: improve documentation of pg_signal_backend default role.
Give it an explanatory para like the other default roles have.
Don't imply that it can send any signal whatever.

In passing, reorder the table entries and explanatory paras
for the default roles into some semblance of consistency.

Ian Barwick, tweaked a bit by me.

Discussion: https://postgr.es/m/89907e32-76f3-7282-a89c-ea19c722fe5d@2ndquadrant.com
2019-08-27 18:03:09 -04:00
Tom Lane c9bd7f4f2b Improve what pg_strsignal prints if we haven't got strsignal(3).
Turns out that returning "unrecognized signal" is confusing.
Make it explicit that the platform lacks any support for signal names.
(At least of the machines in the buildfarm, only HPUX lacks it.)

Back-patch to v12 where we invented this function.

Discussion: https://postgr.es/m/3067.1566870481@sss.pgh.pa.us
2019-08-27 17:24:47 -04:00
Peter Geoghegan b8b3a276d4 Remove obsolete nbtree page deletion comment.
Commit efada2b8e9, which made the nbtree page deletion algorithm more
robust, removed the concept of a half-dead internal page.  Remove a
comment about half dead parent pages that was overlooked.
2019-08-27 14:01:43 -07:00