rdelaage/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-08-25 12:47:18 +02:00
Code Issues Packages Projects Releases Wiki Activity
48,115 Commits 36 Branches 606 Tags 423 MiB
C 86%
PLpgSQL 5.5%
Perl 4.1%
Yacc 1.3%
Makefile 0.7%
Other 2.3%
8b7ae5a82d
Go to file
Tom Lane 8b7ae5a82d Stabilize the results of pg_notification_queue_usage(). 
This function wasn't touched in commit 51004c717, but that turns out
to be a bad idea, because its results now include any dead space
that exists in the NOTIFY queue on account of our being lazy about
advancing the queue tail.  Notably, the isolation tests now fail
if run twice without a server restart between, because async-notify's
first test of the function will already show a positive value.
It seems likely that end users would be equally unhappy about the
result's instability.  To fix, just make the function call
asyncQueueAdvanceTail before computing its result.  That should end
in producing the same value as before, and it's hard to believe that
there's any practical use-case where pg_notification_queue_usage()
is called so often as to create a performance degradation, especially
compared to what we did before.

Out of paranoia, also mark this function parallel-restricted (it
was volatile, but parallel-safe by default, before).  Although the
code seems to work fine when run in a parallel worker, that's outside
the design scope of async.c, and it's a bit scary to have intentional
side-effects happening in a parallel worker.  There seems no plausible
use-case where it'd be important to try to parallelize this, so let's
not take any risk of introducing new bugs.

In passing, re-pgindent async.c and run reformat-dat-files on
pg_proc.dat, just because I'm a neatnik.

Discussion: https://postgr.es/m/13881.1574557302@sss.pgh.pa.us
2019-11-24 14:09:33 -05:00
config Simplify PGAC_STRUCT_TIMEZONE Autoconf macro 2019-10-07 16:47:23 +02:00
contrib Update sepgsql to add mandatory access control for TRUNCATE 2019-11-23 10:46:44 -05:00
doc Make psql redisplay the query buffer after \e. 2019-11-22 17:07:54 -05:00
src Stabilize the results of pg_notification_queue_usage(). 2019-11-24 14:09:33 -05:00
.dir-locals.el Make Emacs perl-mode indent more like perltidy. 2019-01-13 11:32:31 -08:00
.gitattributes gitattributes: Add new file 2019-11-12 08:13:55 +01:00
.gitignore Support for optimizing and emitting code in LLVM JIT provider. 2018-03-22 11:05:22 -07:00
aclocal.m4 Fix configure's AC_CHECK_DECLS tests to work correctly with clang. 2018-11-19 12:01:47 -05:00
configure Remove configure --disable-float4-byval 2019-11-21 18:29:21 +01:00
configure.in Remove configure --disable-float4-byval 2019-11-21 18:29:21 +01:00
COPYRIGHT Update copyright for 2019 2019-01-02 12:44:25 -05:00
GNUmakefile.in Add "headerscheck" script to test header-file compilability under C. 2019-08-19 14:22:56 -04:00
HISTORY Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00
Makefile Don't unset MAKEFLAGS in non-GNU Makefile. 2019-06-25 09:36:21 +12:00
README Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00
README.git Change documentation references to PG website to use https: not http: 2017-05-20 21:50:47 -04:00

README 

PostgreSQL Database Management System
=====================================

This directory contains the source code distribution of the PostgreSQL
database management system.

PostgreSQL is an advanced object-relational database management system
that supports an extended subset of the SQL standard, including
transactions, foreign keys, subqueries, triggers, user-defined types
and functions.  This distribution also contains C language bindings.

PostgreSQL has many language interfaces, many of which are listed here:

	https://www.postgresql.org/download

See the file INSTALL for instructions on how to build and install
PostgreSQL.  That file also lists supported operating systems and
hardware platforms and contains information regarding any other
software packages that are required to build or run the PostgreSQL
system.  Copyright and license information can be found in the
file COPYRIGHT.  A comprehensive documentation set is included in this
distribution; it can be read as described in the installation
instructions.

The latest version of this software may be obtained at
https://www.postgresql.org/download/.  For more information look at our
web site located at https://www.postgresql.org/.