Commit graph

7054 commits

Author SHA1 Message Date
Tom Lane
41b45576d5 Remove useless pfree()s at the ends of various ValuePerCall SRFs.
We don't need to manually clean up allocations in a SRF's
multi_call_memory_ctx, because the SRF_RETURN_DONE infrastructure
takes care of that (and also ensures that it will happen even if the
function never gets a final call, which simple manual cleanup cannot
do).

Hence, the code removed by this patch is a waste of code and cycles.
Worse, it gives the impression that cleaning up manually is a thing,
which can lead to more serious errors such as those fixed in
commits 085b6b667 and b4570d33a.  So we should get rid of it.

These are not quite actual bugs though, so I couldn't muster the
enthusiasm to back-patch.  Fix in HEAD only.

Justin Pryzby

Discussion: https://postgr.es/m/20200308173103.GC1357@telsasoft.com
2020-03-16 21:36:53 -04:00
Tom Lane
b4570d33aa Avoid holding a directory FD open across assorted SRF calls.
This extends the fixes made in commit 085b6b667 to other SRFs with the
same bug, namely pg_logdir_ls(), pgrowlocks(), pg_timezone_names(),
pg_ls_dir(), and pg_tablespace_databases().

Also adjust various comments and documentation to warn against
expecting to clean up resources during a ValuePerCall SRF's final
call.

Back-patch to all supported branches, since these functions were
all born broken.

Justin Pryzby, with cosmetic tweaks by me

Discussion: https://postgr.es/m/20200308173103.GC1357@telsasoft.com
2020-03-16 21:05:52 -04:00
Thomas Munro
fc34b0d9de Introduce a maintenance_io_concurrency setting.
Introduce a GUC and a tablespace option to control I/O prefetching, much
like effective_io_concurrency, but for work that is done on behalf of
many client sessions.

Use the new setting in heapam.c instead of the hard-coded formula
effective_io_concurrency + 10 introduced by commit 558a9165e0.  Go with
a default value of 10 for now, because it's a round number pretty close
to the value used for that existing case.

Discussion: https://postgr.es/m/CA%2BhUKGJUw08dPs_3EUcdO6M90GnjofPYrWp4YSLaBkgYwS-AqA%40mail.gmail.com
2020-03-16 17:14:26 +13:00
Thomas Munro
b09ff53667 Simplify the effective_io_concurrency setting.
The effective_io_concurrency GUC and equivalent tablespace option were
previously passed through a formula based on a theory about RAID
spindles and probabilities, to arrive at the number of pages to prefetch
in bitmap heap scans.  Tomas Vondra, Andres Freund and others argued
that it was anachronistic and hard to justify, and commit 558a9165e0
already started down the path of bypassing it in new code.  We agreed to
drop that logic and use the value directly.

For the default setting of 1, there is no change in effect.  Higher
settings can be converted from the old meaning to the new with:

  select round(sum(OLD / n::float)) from generate_series(1, OLD) s(n);

We might want to consider renaming the GUC before the next release given
the change in meaning, but it's not clear that many users had set it
very carefully anyway.  That decision is deferred for now.

Discussion: https://postgr.es/m/CA%2BhUKGJUw08dPs_3EUcdO6M90GnjofPYrWp4YSLaBkgYwS-AqA%40mail.gmail.com
2020-03-16 17:14:26 +13:00
Peter Eisentraut
70a7b4776b Add backend type to csvlog and optionally log_line_prefix
The backend type, which corresponds to what
pg_stat_activity.backend_type shows, is added as a column to the
csvlog and can optionally be added to log_line_prefix using the new %b
placeholder.

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://www.postgresql.org/message-id/flat/c65e5196-4f04-4ead-9353-6088c19615a3@2ndquadrant.com
2020-03-15 11:20:21 +01:00
Tom Lane
87c9c2571c Rearrange pseudotypes.c to get rid of duplicative code.
Commit a5954de10 replaced a lot of manually-coded stub I/O routines
with code generated by macros.  That was a good idea but it didn't
go far enough, because there were still manually-coded stub input
routines for types that had live output routines.  Refactor the
macro so that we can generate just a stub input routine at need.

Also create similar macros to generate stub binary I/O routines,
since we have some of those now.  The only stub functions that remain
hand-coded are shell_in() and shell_out(), which need to be separate
because they use different error messages.

While here, rearrange the commentary to discuss each type not each
function.  This provides a better way to explain the *why* of which
types need which support, rather than just duplicatively annotating
the functions.

Discussion: https://postgr.es/m/24137.1584139352@sss.pgh.pa.us
2020-03-14 15:31:44 -04:00
Tom Lane
4dbcb3f844 Restructure polymorphic-type resolution in funcapi.c.
resolve_polymorphic_tupdesc() and resolve_polymorphic_argtypes() failed to
cover the case of having to resolve anyarray given only an anyrange input.
The bug was masked if anyelement was also used (as either input or
output), which probably helps account for our not having noticed.

While looking at this I noticed that resolve_generic_type() would produce
the wrong answer if asked to make that same resolution.  ISTM that
resolve_generic_type() is confusingly defined and overly complex, so
rather than fix it, let's just make funcapi.c do the specific lookups
it requires for itself.

With this change, resolve_generic_type() is not used anywhere, so remove
it in HEAD.  In the back branches, leave it alone (complete with bug)
just in case any external code is using it.

While we're here, make some other refactoring adjustments in funcapi.c
with an eye to upcoming future expansion of the set of polymorphic types:

* Simplify quick-exit tests by adding an overall have_polymorphic_result
flag.  This is about a wash now but will be a win when there are more
flags.

* Reduce duplication of code between resolve_polymorphic_tupdesc() and
resolve_polymorphic_argtypes().

* Don't bother to validate correct matching of anynonarray or anyenum;
the parser should have done that, and even if it didn't, just doing
"return false" here would lead to a very confusing, off-point error
message.  (Really, "return false" in these two functions should only
occur if the call_expr isn't supplied or we can't obtain data type
info from it.)

* For the same reason, throw an elog rather than "return false" if
we fail to resolve a polymorphic type.

The bug's been there since we added anyrange, so back-patch to
all supported branches.

Discussion: https://postgr.es/m/6093.1584202130@sss.pgh.pa.us
2020-03-14 14:42:22 -04:00
Peter Eisentraut
d90bd24391 Remove am_syslogger global variable
Use the new MyBackendType instead.  More similar changes for other "am
something" variables are possible.  This one was just particularly
simple.

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/c65e5196-4f04-4ead-9353-6088c19615a3@2ndquadrant.com
2020-03-13 14:01:15 +01:00
Peter Eisentraut
8e8a0becb3 Unify several ways to tracking backend type
Add a new global variable MyBackendType that uses the same BackendType
enum that was previously only used by the stats collector.  That way
several duplicate ways of checking what type a particular process is
can be simplified.  Since it's no longer just for stats, move to
miscinit.c and rename existing functions to match the expanded
purpose.

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/c65e5196-4f04-4ead-9353-6088c19615a3@2ndquadrant.com
2020-03-13 14:01:10 +01:00
Peter Eisentraut
1cc9c2412c Preserve replica identity index across ALTER TABLE rewrite
If an index was explicitly set as replica identity index, this setting
was lost when a table was rewritten by ALTER TABLE.  Because this
setting is part of pg_index but actually controlled by ALTER
TABLE (not part of CREATE INDEX, say), we have to do some extra work
to restore it.

Based-on-patch-by: Quan Zongliang <quanzongliang@gmail.com>
Reviewed-by: Euler Taveira <euler.taveira@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/c70fcab2-4866-0d9f-1d01-e75e189db342@gmail.com
2020-03-13 11:57:06 +01:00
Tom Lane
085b6b6679 Avoid holding a directory FD open across pg_ls_dir_files() calls.
This coding technique is undesirable because (a) it leaks the FD for
the rest of the transaction if the SRF is not run to completion, and
(b) allocated FDs are a scarce resource, but multiple interleaved
uses of the relevant functions could eat many such FDs.

In v11 and later, a query such as "SELECT pg_ls_waldir() LIMIT 1"
yields a warning about the leaked FD, and the only reason there's
no warning in earlier branches is that fd.c didn't whine about such
leaks before commit 9cb7db3f0.  Even disregarding the warning, it
wouldn't be too hard to run a backend out of FDs with careless use
of these SQL functions.

Hence, rewrite the function so that it reads the directory within
a single call, returning the results as a tuplestore rather than
via value-per-call mode.

There are half a dozen other built-in SRFs with similar problems,
but let's fix this one to start with, just to see if the buildfarm
finds anything wrong with the code.

In passing, fix bogus error report for stat() failure: it was
whining about the directory when it should be fingering the
individual file.  Doubtless a copy-and-paste error.

Back-patch to v10 where this function was added.

Justin Pryzby, with cosmetic tweaks and test cases by me

Discussion: https://postgr.es/m/20200308173103.GC1357@telsasoft.com
2020-03-11 15:27:59 -04:00
Peter Eisentraut
bf68b79e50 Refactor ps_status.c API
The init_ps_display() arguments were mostly lies by now, so to match
typical usage, just use one argument and let the caller assemble it
from multiple sources if necessary.  The only user of the additional
arguments is BackendInitialize(), which was already doing string
assembly on the caller side anyway.

Remove the second argument of set_ps_display() ("force") and just
handle that in init_ps_display() internally.

BackendInitialize() also used to set the initial status as
"authentication", but that was very far from where authentication
actually happened.  So now it's set to "initializing" and then
"authentication" just before the actual call to
ClientAuthentication().

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Kuntal Ghosh <kuntalghosh.2007@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/c65e5196-4f04-4ead-9353-6088c19615a3@2ndquadrant.com
2020-03-11 16:38:31 +01:00
Peter Eisentraut
1c91838181 Clean up order in miscinit.c a bit
The code around InitPostmasterChild() from commit 31c453165b somehow
ended up in the middle of a block of code related to "User ID state".
Move it into its own block instead.
2020-03-11 13:51:55 +01:00
Tom Lane
c8e8b2f9df Marginal comments and docs cleanup.
Fix up some imprecise comments and poor markup from ba79cb5dc.  Also try
to convert the documentation of log_min_duration_sample and friends into
passable English.
2020-03-10 17:34:09 -04:00
Alvaro Herrera
40b3e2c201
Split out CreateCast into src/backend/catalog/pg_cast.c
This catalog-handling code was previously together with the rest of
CastCreate() in src/backend/commands/functioncmds.c.  A future patch
will need a way to add casts internally, so this will be useful to have
separate.

Also, move the nearby get_cast_oid() function from functioncmds.c to
lsyscache.c, which seems a more natural place for it.

Author: Paul Jungwirth, minor edits by Álvaro
Discussion: https://postgr.es/m/20200309210003.GA19992@alvherre.pgsql
2020-03-10 11:28:23 -03:00
Peter Eisentraut
3c173a53a8 Remove utils/acl.h from catalog/objectaddress.h
The need for this was removed by
8b9e9644dc.

A number of files now need to include utils/acl.h or
parser/parse_node.h explicitly where they previously got it indirectly
somehow.

Since parser/parse_node.h already includes nodes/parsenodes.h, the
latter is then removed where the former was added.  Also, remove
nodes/pg_list.h from objectaddress.h, since that's included via
nodes/parsenodes.h.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/7601e258-26b2-8481-36d0-dc9dca6f28f1%402ndquadrant.com
2020-03-10 10:27:00 +01:00
Michael Paquier
61d7c7bce3 Prevent reindex of invalid indexes on TOAST tables
Such indexes can only be duplicated leftovers of a previously failed
REINDEX CONCURRENTLY command, and a valid equivalent is guaranteed to
exist.  As toast indexes can only be dropped if invalid, reindexing
these would lead to useless duplicated indexes that can't be dropped
anymore, except if the parent relation is dropped.

Thanks to Justin Pryzby for reminding that this problem was reported
long ago during the review of the original patch of REINDEX
CONCURRENTLY, but the issue was never addressed.

Reported-by: Sergei Kornilov, Justin Pryzby
Author: Julien Rouhaud
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/36712441546604286%40sas1-890ba5c2334a.qloud-c.yandex.net
Discussion: https://postgr.es/m/20200216190835.GA21832@telsasoft.com
Backpatch-through: 12
2020-03-10 15:38:17 +09:00
Jeff Davis
24d85952a5 Introduce LogicalTapeSetExtend().
Increases the number of tapes in a logical tape set. This will be
important for disk-based hash aggregation, because the maximum number
of tapes is not known ahead of time.

While discussing this change, it was observed to regress the
performance of Sort for at least one test case. The performance
regression was because some versions of GCC switch to an inlined
version of memcpy() in LogicalTapeWrite() after this change. No
performance regression for clang was observed.

Because the regression is due to an arbitrary decision by the
compiler, I decided it shouldn't hold up this change. If it needs to
be fixed, we can find a workaround.

Author: Adam Lee, Jeff Davis
Discussion: https://postgr.es/m/e54bfec11c59689890f277722aaaabd05f78e22c.camel%40j-davis.com
2020-03-09 10:40:02 -07:00
Peter Eisentraut
71d60e2aa0 Add tg_updatedcols to TriggerData
This allows a trigger function to determine for an UPDATE trigger
which columns were actually updated.  This allows some optimizations
in generic trigger functions such as lo_manage and
tsvector_update_trigger.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/flat/11c5f156-67a9-0fb5-8200-2a8018eb2e0c@2ndquadrant.com
2020-03-09 09:34:55 +01:00
Fujii Masao
d9249441ef Mark ssl_passphrase_command as GUC_SUPERUSER_ONLY.
This commit changes the GUC ssl_passphrase_command so that
it's examinable by only superuser and a member of pg_read_all_settings.
Per discussion, we determined to do this because the parameter may
contain a sensitive informtaion like a passphrase itself.

Author: Insung Moon
Reviewed-by: Keisuke Kuroda
Discussion: https://postgr.es/m/CAEMmqBuHVGayc+QkYKgx3gWSdqwTAQGw+0DYn3WhcX-eNa2ntA@mail.gmail.com
2020-03-09 11:41:31 +09:00
Tom Lane
a6525588b7 Allow Unicode escapes in any server encoding, not only UTF-8.
SQL includes provisions for numeric Unicode escapes in string
literals and identifiers.  Previously we only accepted those
if they represented ASCII characters or the server encoding
was UTF-8, making the conversion to internal form trivial.
This patch adjusts things so that we'll call the appropriate
encoding conversion function in less-trivial cases, allowing
the escape sequence to be accepted so long as it corresponds
to some character available in the server encoding.

This also applies to processing of Unicode escapes in JSONB.
However, the old restriction still applies to client-side
JSON processing, since that hasn't got access to the server's
encoding conversion infrastructure.

This patch includes some lexer infrastructure that simplifies
throwing errors with error cursors pointing into the middle of
a string (or other complex token).  For the moment I only used
it for errors relating to Unicode escapes, but we might later
expand the usage to some other cases.

Patch by me, reviewed by John Naylor.

Discussion: https://postgr.es/m/2393.1578958316@sss.pgh.pa.us
2020-03-06 14:17:43 -05:00
Tom Lane
fe30e7ebfa Allow ALTER TYPE to change some properties of a base type.
Specifically, this patch allows ALTER TYPE to:
* Change the default TOAST strategy for a toastable base type;
* Promote a non-toastable type to toastable;
* Add/remove binary I/O functions for a type;
* Add/remove typmod I/O functions for a type;
* Add/remove a custom ANALYZE statistics functions for a type.

The first of these can be done by the type's owner; all the others
require superuser privilege since misuse could cause problems.

The main motivation for this patch is to allow extensions to
upgrade the feature sets of their data types, so the set of
alterable properties is biased towards that use-case.  However
it's also true that changing some other properties would be
a lot harder, as they get baked into physical storage and/or
stored expressions that depend on the type.

Along the way, refactor GenerateTypeDependencies() to make it easier
to call, refactor DefineType's volatility checks so they can be shared
by AlterType, and teach typcache.c that it might have to reload data
from the type's pg_type row, a scenario it never handled before.
Also rearrange alter_type.sgml a bit for clarity (put the
composite-type operations together).

Tomas Vondra and Tom Lane

Discussion: https://postgr.es/m/20200228004440.b23ein4qvmxnlpht@development
2020-03-06 12:19:29 -05:00
Tom Lane
bb03010b9f Remove the "opaque" pseudo-type and associated compatibility hacks.
A long time ago, it was necessary to declare datatype I/O functions,
triggers, and language handler support functions in a very type-unsafe
way involving a single pseudo-type "opaque".  We got rid of those
conventions in 7.3, but there was still support in various places to
automatically convert such functions to the modern declaration style,
to be able to transparently re-load dumps from pre-7.3 servers.
It seems unnecessary to continue to support that anymore, so take out
the hacks; whereupon the "opaque" pseudo-type itself is no longer
needed and can be dropped.

This is part of a group of patches removing various server-side kluges
for transparently upgrading pre-8.0 dump files.  Since we've had few
complaints about dropping pg_dump's support for dumping from pre-8.0
servers (commit 64f3524e2), it seems okay to now remove these kluges.

Discussion: https://postgr.es/m/4110.1583255415@sss.pgh.pa.us
2020-03-05 15:48:56 -05:00
Alvaro Herrera
a77315fdf2
Remove RangeIOData->typiofunc
We used to carry the I/O function OID in RangeIOData, but it's not used
for anything.  Since the struct is not exposed to the world anyway, we
can simplify it a bit.  Also, rename the FmgrInfo member to match
the accompanying 'typioparam' and put them in a more sensible order.

Reviewed by Tom Lane and Paul Jungwirth.

Discussion: https://postgr.es/m/20200304215711.GA8732@alvherre.pgsql
2020-03-05 11:35:02 -03:00
Tom Lane
3ed2005ff5 Introduce macros for typalign and typstorage constants.
Our usual practice for "poor man's enum" catalog columns is to define
macros for the possible values and use those, not literal constants,
in C code.  But for some reason lost in the mists of time, this was
never done for typalign/attalign or typstorage/attstorage.  It's never
too late to make it better though, so let's do that.

The reason I got interested in this right now is the need to duplicate
some uses of the TYPSTORAGE constants in an upcoming ALTER TYPE patch.
But in general, this sort of change aids greppability and readability,
so it's a good idea even without any specific motivation.

I may have missed a few places that could be converted, and it's even
more likely that pending patches will re-introduce some hard-coded
references.  But that's not fatal --- there's no expectation that
we'd actually change any of these values.  We can clean up stragglers
over time.

Discussion: https://postgr.es/m/16457.1583189537@sss.pgh.pa.us
2020-03-04 10:34:25 -05:00
Tom Lane
d677550493 Allow to_date/to_timestamp to recognize non-English month/day names.
to_char() has long allowed the TM (translation mode) prefix to
specify output of translated month or day names; but that prefix
had no effect in input format strings.  Now it does.  to_date()
and to_timestamp() will now recognize the same month or day names
that to_char() would output for the same format code.  Matching is
case-insensitive (per the active collation's notion of what that
means), just as it has always been for English month/day names
without the TM prefix.

(As per the discussion thread, there are lots of cases that this
feature will not handle, such as alternate day names.  But being
able to accept what to_char() will output seems useful enough.)

In passing, fix some shaky English and violations of message
style guidelines in jsonpath errors for the .datetime() method,
which depends on this code.

Juan José Santamaría Flecha, reviewed and modified by me,
with other commentary from Alvaro Herrera, Tomas Vondra,
Arthur Zakirov, Peter Eisentraut, Mark Dilger.

Discussion: https://postgr.es/m/CAC+AXB3u1jTngJcoC1nAHBf=M3v-jrEfo86UFtCqCjzbWS9QhA@mail.gmail.com
2020-03-03 11:06:47 -05:00
Fujii Masao
e65497df8f Report progress of streaming base backup.
This commit adds pg_stat_progress_basebackup view that reports
the progress while an application like pg_basebackup is taking
a base backup. This uses the progress reporting infrastructure
added by c16dc1aca5, adding support for streaming base backup.

Bump catversion.

Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Amit Langote, Sergei Kornilov
Discussion: https://postgr.es/m/9ed8b801-8215-1f3d-62d7-65bff53f6e94@oss.nttdata.com
2020-03-03 12:03:43 +09:00
Alvaro Herrera
2f9661311b
Represent command completion tags as structs
The backend was using strings to represent command tags and doing string
comparisons in multiple places, but that's slow and unhelpful.  Create a
new command list with a supporting structure to use instead; this is
stored in a tag-list-file that can be tailored to specific purposes with
a caller-definable C macro, similar to what we do for WAL resource
managers.  The first first such uses are a new CommandTag enum and a
CommandTagBehavior struct.

Replace numerous occurrences of char *completionTag with a
QueryCompletion struct so that the code no longer stores information
about completed queries in a cstring.  Only at the last moment, in
EndCommand(), does this get converted to a string.

EventTriggerCacheItem no longer holds an array of palloc’d tag strings
in sorted order, but rather just a Bitmapset over the CommandTags.

Author: Mark Dilger, with unsolicited help from Álvaro Herrera
Reviewed-by: John Naylor, Tom Lane
Discussion: https://postgr.es/m/981A9DB4-3F0C-4DA5-88AD-CB9CFF4D6CAD@enterprisedb.com
2020-03-02 18:19:51 -03:00
Dean Rasheed
43a899f41f Fix corner-case loss of precision in numeric ln().
When deciding on the local rscale to use for the Taylor series
expansion, ln_var() neglected to account for the fact that the result
is subsequently multiplied by a factor of 2^(nsqrt+1), where nsqrt is
the number of square root operations performed in the range reduction
step, which can be as high as 22 for very large inputs. This could
result in a loss of precision, particularly when combined with large
rscale values, for which a large number of Taylor series terms is
required (up to around 400).

Fix by computing a few extra digits in the Taylor series, based on the
weight of the multiplicative factor log10(2^(nsqrt+1)). It remains to
be proven whether or not the other 8 extra digits used for the Taylor
series is appropriate, but this at least deals with the obvious
oversight of failing to account for the effects of the final
multiplication.

Per report from Justin AnyhowStep. Reviewed by Tom Lane.

Discussion: https://postgr.es/m/16280-279f299d9c06e56f@postgresql.org
2020-03-01 14:49:25 +00:00
Robert Haas
05d8449e73 Move src/backend/utils/hash/hashfn.c to src/common
This also involves renaming src/include/utils/hashutils.h, which
becomes src/include/common/hashfn.h. Perhaps an argument can be
made for keeping the hashutils.h name, but it seemed more
consistent to make it match the name of the file, and also more
descriptive of what is actually going on here.

Patch by me, reviewed by Suraj Kharage and Mark Dilger. Off-list
advice on how not to break the Windows build from Davinder Singh
and Amit Kapila.

Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
2020-02-27 09:25:41 +05:30
Peter Geoghegan
612a1ab767 Add equalimage B-Tree support functions.
Invent the concept of a B-Tree equalimage ("equality implies image
equality") support function, registered as support function 4.  This
indicates whether it is safe (or not safe) to apply optimizations that
assume that any two datums considered equal by an operator class's order
method must be interchangeable without any loss of semantic information.
This is static information about an operator class and a collation.

Register an equalimage routine for almost all of the existing B-Tree
opclasses.  We only need two trivial routines for all of the opclasses
that are included with the core distribution.  There is one routine for
opclasses that index non-collatable types (which returns 'true'
unconditionally), plus another routine for collatable types (which
returns 'true' when the collation is a deterministic collation).

This patch is infrastructure for an upcoming patch that adds B-Tree
deduplication.

Author: Peter Geoghegan, Anastasia Lubennikova
Discussion: https://postgr.es/m/CAH2-Wzn3Ee49Gmxb7V1VJ3-AC8fWn-Fr8pfWQebHe8rYRxt5OQ@mail.gmail.com
2020-02-26 11:28:25 -08:00
Tom Lane
3d475515a1 Account explicitly for long-lived FDs that are allocated outside fd.c.
The comments in fd.c have long claimed that all file allocations should
go through that module, but in reality that's not always practical.
fd.c doesn't supply APIs for invoking some FD-producing syscalls like
pipe() or epoll_create(); and the APIs it does supply for non-virtual
FDs are mostly insistent on releasing those FDs at transaction end;
and in some cases the actual open() call is in code that can't be made
to use fd.c, such as libpq.

This has led to a situation where, in a modern server, there are likely
to be seven or so long-lived FDs per backend process that are not known
to fd.c.  Since NUM_RESERVED_FDS is only 10, that meant we had *very*
few spare FDs if max_files_per_process is >= the system ulimit and
fd.c had opened all the files it thought it safely could.  The
contrib/postgres_fdw regression test, in particular, could easily be
made to fall over by running it under a restrictive ulimit.

To improve matters, invent functions Acquire/Reserve/ReleaseExternalFD
that allow outside callers to tell fd.c that they have or want to allocate
a FD that's not directly managed by fd.c.  Add calls to track all the
fixed FDs in a standard backend session, so that we are honestly
guaranteeing that NUM_RESERVED_FDS FDs remain unused below the EMFILE
limit in a backend's idle state.  The coding rules for these functions say
that there's no need to call them in code that just allocates one FD over
a fairly short interval; we can dip into NUM_RESERVED_FDS for such cases.
That means that there aren't all that many places where we need to worry.
But postgres_fdw and dblink must use this facility to account for
long-lived FDs consumed by libpq connections.  There may be other places
where it's worth doing such accounting, too, but this seems like enough
to solve the immediate problem.

Internally to fd.c, "external" FDs are limited to max_safe_fds/3 FDs.
(Callers can choose to ignore this limit, but of course it's unwise
to do so except for fixed file allocations.)  I also reduced the limit
on "allocated" files to max_safe_fds/3 FDs (it had been max_safe_fds/2).
Conceivably a smarter rule could be used here --- but in practice,
on reasonable systems, max_safe_fds should be large enough that this
isn't much of an issue, so KISS for now.  To avoid possible regression
in the number of external or allocated files that can be opened,
increase FD_MINFREE and the lower limit on max_files_per_process a
little bit; we now insist that the effective "ulimit -n" be at least 64.

This seems like pretty clearly a bug fix, but in view of the lack of
field complaints, I'll refrain from risking a back-patch.

Discussion: https://postgr.es/m/E1izCmM-0005pV-Co@gemulon.postgresql.org
2020-02-24 17:28:33 -05:00
Robert Haas
a91e2fa941 Adapt hashfn.c and hashutils.h for frontend use.
hash_any() and its various variants are defined to return Datum,
which is a backend-only concept, but the underlying functions
actually want to return uint32 and uint64, and only return Datum
because it's convenient for callers who are using them to
implement a hash function for some SQL datatype.

However, changing these functions to return uint32 and uint64
seems like it might lead to programming errors or back-patching
difficulties, both because they are widely used and because
failure to use UInt{32,64}GetDatum() might not provoke a
compilation error. Instead, rename the existing functions as
well as changing the return type, and add static inline wrappers
for those callers that need the previous behavior.

Although this commit adapts hashutils.h and hashfn.c so that they
can be compiled as frontend code, it does not actually do
anything that would cause them to be so compiled. That is left
for another commit.

Patch by me, reviewed by Suraj Kharage and Mark Dilger.

Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
2020-02-24 17:27:15 +05:30
Robert Haas
9341c783cc Put all the prototypes for hashfn.c into the same header file.
Previously, some of the prototypes for functions in hashfn.c were
in utils/hashutils.h and others were in utils/hsearch.h, but that
is confusing and has no particular benefit.

Patch by me, reviewed by Suraj Kharage and Mark Dilger.

Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
2020-02-24 17:22:45 +05:30
Robert Haas
07b95c3d83 Move bitmap_hash and bitmap_match to bitmapset.c.
The closely-related function bms_hash_value is already defined in that
file, and this change means that hashfn.c no longer needs to depend on
nodes/bitmapset.h. That gets us closer to allowing use of the hash
functions in hashfn.c in frontend code.

Patch by me, reviewed by Suraj Kharage and Mark Dilger.

Discussion: http://postgr.es/m/CA+TgmoaRiG4TXND8QuM6JXFRkM_1wL2ZNhzaUKsuec9-4yrkgw@mail.gmail.com
2020-02-24 17:17:43 +05:30
Tom Lane
97cf1fa4ed Assume that we have <wchar.h>.
Windows has this, and so do all other live platforms according to the
buildfarm; it's been required by POSIX since SUSv2.  So remove the
configure probe and tests of HAVE_WCHAR_H.

This is part of a series of commits to get rid of no-longer-relevant
configure checks and dead src/port/ code.  I'm committing them separately
to make it easier to back out individual changes if they prove less
portable than I expect.

Discussion: https://postgr.es/m/15379.1582221614@sss.pgh.pa.us
2020-02-21 14:30:47 -05:00
Tom Lane
481c8e9232 Assume that we have utime() and <utime.h>.
These are required by POSIX since SUSv2, and no live platforms fail
to provide them.  On Windows, utime() exists and we bring our own
<utime.h>, so we're good there too.  So remove the configure probes
and ad-hoc substitute code.  We don't need to check for utimes()
anymore either, since that was only used as a substitute.

In passing, make the Windows build include <sys/utime.h> only where
we need it, not everywhere.

This is part of a series of commits to get rid of no-longer-relevant
configure checks and dead src/port/ code.  I'm committing them separately
to make it easier to back out individual changes if they prove less
portable than I expect.

Discussion: https://postgr.es/m/15379.1582221614@sss.pgh.pa.us
2020-02-21 14:30:47 -05:00
Tom Lane
abe41f453a Assume that we have cbrt().
Windows has this, and so do all other live platforms according to the
buildfarm, so remove the configure probe and float.c's substitute code.

This is part of a series of commits to get rid of no-longer-relevant
configure checks and dead src/port/ code.  I'm committing them separately
to make it easier to back out individual changes if they prove less
portable than I expect.

Discussion: https://postgr.es/m/15379.1582221614@sss.pgh.pa.us
2020-02-21 14:30:47 -05:00
Jeff Davis
8021985d79 logtape.c: allocate read buffer even for an empty tape.
Prior to this commit, the read buffer was allocated at the time the tape
was rewound; but as an optimization, would not be allocated at all if
the tape was empty.

That optimization meant that it was valid to have a rewound tape with
the buffer set to NULL, but only if a number of conditions were met
and only if the API was used properly. After 7fdd919a refactored the
code to support lazily-allocating the buffer, Coverity started
complaining.

The optimization for empty tapes doesn't seem important, so just
allocate the buffer whether the tape has any data or not.

Discussion: https://postgr.es/m/20351.1581868306%40sss.pgh.pa.us
2020-02-19 10:04:17 -08:00
Michael Paquier
958f9fb98d Remove duplicated words in comments
Author: Daniel Gustafsson
Reviewed-by: Vik Fearing
Discussion: https://postgr.es/m/EBC3BFEB-664C-4063-81ED-29F1227DB012@yesql.se
2020-02-18 12:20:55 +09:00
Jeff Davis
7fdd919ae7 Logical Tape Set: lazily allocate read buffer.
The write buffer was already lazily-allocated, so this is more
symmetric. It also means that a freshly-rewound tape (whether for
reading or writing) is not consuming memory for the buffer.

Discussion: https://postgr.es/m/97c46a59c27f3c38e486ca170fcbc618d97ab049.camel%40j-davis.com
2020-02-13 10:44:25 -08:00
Tom Lane
607f8ce74d Avoid a performance regression in float overflow/underflow detection.
Commit 6bf0bc842 replaced float.c's CHECKFLOATVAL() macro with static
inline subroutines, but that wasn't too well thought out.  In the original
coding, the unlikely condition (isinf(result) or result == 0) was checked
first, and the inf_is_valid or zero_is_valid condition only afterwards.
The inline-subroutine coding caused that to be swapped around, which is
pretty horrid for performance because (a) in common cases the is_valid
condition is twice as expensive to evaluate (e.g., requiring two isinf()
calls not one) and (b) in common cases the is_valid condition is false,
requiring us to perform the unlikely-condition check anyway.  Net result
is that one isinf() call becomes two or three, resulting in visible
performance loss as reported by Keisuke Kuroda.

The original fix proposal was to revert the replacement of the macro,
but on second thought, that macro was just a bad idea from the beginning:
if anything it's a net negative for readability of the code.  So instead,
let's just open-code all the overflow/underflow tests, being careful to
test the unlikely condition first (and mark it unlikely() to help the
compiler get the point).

Also, rather than having N copies of the actual ereport() calls, collapse
those into out-of-line error subroutines to save some code space.  This
does mean that the error file/line numbers won't be very helpful for
figuring out where the issue really is --- but we'd already burned that
bridge by putting the ereports into static inlines.

In HEAD, check_float[48]_val() are gone altogether.  In v12, leave them
present in float.h but unused in the core code, just in case some
extension is depending on them.

Emre Hasegeli, with some kibitzing from me and Andres Freund

Discussion: https://postgr.es/m/CANDwggLe1Gc1OrRqvPfGE=kM9K0FSfia0hbeFCEmwabhLz95AA@mail.gmail.com
2020-02-13 13:37:43 -05:00
Thomas Munro
701a51fd4e Use pg_pwrite() in more places.
This removes some lseek() system calls.

Author: Thomas Munro
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/CA%2BhUKGJ%2BoHhnvqjn3%3DHro7xu-YDR8FPr0FL6LF35kHRX%3D_bUzg%40mail.gmail.com
2020-02-11 17:50:22 +13:00
Fujii Masao
cb5b28613d Fix bug in Tid scan.
Commit 147e3722f7 changed Tid scan so that it calls table_beginscan()
and uses the scan option for seq scan. This change caused two issues.

(1) The change caused Tid scan to take a predicate lock on the entire
       relation in serializable transaction even when relation-level
       lock is not necessary. This could lead to an unexpected
       serialization error.

(2) The change caused Tid scan to increment the number of seq_scan
       in pg_stat_*_tables views even though it's not seq scan. This
       could confuse the users.

This commit adds the scan option for Tid scan and makes Tid scan
use it, to avoid those issues.

Back-patch to v12, where the bug was introduced.

Author: Tatsuhito Kasahara
Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Fujii Masao
Discussion: https://postgr.es/m/CAP0=ZVKy+gTbFmB6X_UW0pP3WaeJ-fkUWHoD-pExS=at3CY76g@mail.gmail.com
2020-02-07 22:06:31 +09:00
Michael Paquier
414c2fd1e1 Revert "Add GUC checks for ssl_min_protocol_version and ssl_max_protocol_version"
This reverts commit 41aadee, as the GUC checks could run on older values
with the new values used, and result in incorrect errors if both
parameters are changed at the same time.

Per complaint from Tom Lane.

Discussion: https://postgr.es/m/27574.1581015893@sss.pgh.pa.us
Backpatch-through: 12
2020-02-07 08:10:40 +09:00
Peter Eisentraut
fc7a5e9eaa Ensure relcache consistency around generated columns
In certain transient states, it's possible that a table has attributes
with attgenerated set but no default expressions in pg_attrdef yet.
In that case, the old code path would not set
relation->rd_att->constr->has_generated_stored, unless
relation->rd_att->constr was also populated for some other reason.
There was probably no practical impact, but it's better to keep this
consistent.

Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/20200115181105.ad6ab6dlgyww3lb6%40alap3.anarazel.de
2020-02-06 21:25:01 +01:00
Jeff Davis
7d4395d0a1 Refactor hash_agg_entry_size().
Consolidate the calculations for hash table size estimation. This will
help with upcoming Hash Aggregation work that will add additional call
sites.
2020-02-06 11:49:56 -08:00
Jeff Davis
c02fdc9223 Logical Tape Set: use min heap for freelist.
Previously, the freelist of blocks was tracked as an
occasionally-sorted array. A min heap is more resilient to larger
freelists or more frequent changes between reading and writing.

Discussion: https://postgr.es/m/97c46a59c27f3c38e486ca170fcbc618d97ab049.camel%40j-davis.com
2020-02-06 10:09:45 -08:00
Michael Paquier
b025f32e0b Add leader_pid to pg_stat_activity
This new field tracks the PID of the group leader used with parallel
query.  For parallel workers and the leader, the value is set to the
PID of the group leader.  So, for the group leader, the value is the
same as its own PID.  Note that this reflects what PGPROC stores in
shared memory, so as leader_pid is NULL if a backend has never been
involved in parallel query.  If the backend is using parallel query or
has used it at least once, the value is set until the backend exits.

Author: Julien Rouhaud
Reviewed-by: Sergei Kornilov, Guillaume Lelarge, Michael Paquier, Tomas
Vondra
Discussion: https://postgr.es/m/CAOBaU_Yy5bt0vTPZ2_LUM6cUcGeqmYNoJ8-Rgto+c2+w3defYA@mail.gmail.com
2020-02-06 09:18:06 +09:00
Alvaro Herrera
15d13e8291 Make vacuum buffer counters 64 bits wide
Using 32 bit counters means they can now realistically wrap around when
vacuuming extremely large tables.  Because they're signed integers,
stats printed by vacuum look very odd when they do.

We'd love to backpatch this, but refrain because the variables are
exported and could cause third-party code to break.

Reviewed-by: Julien Rouhaud, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/20200131205926.GA16367@alvherre.pgsql
2020-02-05 16:59:29 -03:00