rdelaage/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-10-01 12:51:24 +02:00
Code Issues Packages Projects Releases Wiki Activity
39,032 Commits 36 Branches 606 Tags 423 MiB
C 86%
PLpgSQL 5.5%
Perl 4.1%
Yacc 1.3%
Makefile 0.7%
Other 2.3%
5ddc72887a
Go to file
Kevin Grittner 5ddc72887a Fix an O(N^2) problem in foreign key references. 
Commit 45ba424f improved foreign key lookups during bulk updates
when the FK value does not change.  When restoring a schema dump
from a database with many (say 100,000) foreign keys, this cache
would grow very big and every ALTER TABLE command was causing an
InvalidateConstraintCacheCallBack(), which uses a sequential hash
table scan.  This could cause a severe performance regression in
restoring a schema dump (including during pg_upgrade).

The patch uses a heuristic method of detecting when the hash table
should be destroyed and recreated.
InvalidateConstraintCacheCallBack() adds the current size of the
hash table to a counter.  When that sum reaches 1,000,000, the hash
table is flushed.  This fixes the regression without noticeable
harm to the bulk update use case.

Jan Wieck
Backpatch to 9.3 where the performance regression was introduced.
2015-09-11 13:06:51 -05:00
config Remove support for Unix systems without the POSIX signal APIs. 2015-08-31 12:56:10 -04:00
contrib Fix error message wording in previous sslinfo commit 2015-09-08 11:10:20 -03:00
doc Correct description of PageHeaderData layout in documentation 2015-09-11 13:02:15 +09:00
src Fix an O(N^2) problem in foreign key references. 2015-09-11 13:06:51 -05:00
.dir-locals.el emacs: Set indent-tabs-mode in perl-mode 2015-04-12 23:53:23 -04:00
.gitattributes Add functions for dealing with PGP armor header lines to pgcrypto. 2014-10-01 16:03:39 +03:00
.gitignore Add .gitignore entries for AIX-specific intermediate build artifacts. 2015-07-08 20:44:22 -04:00
aclocal.m4 Replace our hacked version of ax_pthread.m4 with latest upstream version. 2015-07-08 20:36:06 +03:00
configure Remove support for Unix systems without the POSIX signal APIs. 2015-08-31 12:56:10 -04:00
configure.in Remove support for Unix systems without the POSIX signal APIs. 2015-08-31 12:56:10 -04:00
COPYRIGHT Update copyright for 2015 2015-01-06 11:43:47 -05:00
GNUmakefile.in Fix distclean/maintainer-clean targets to remove top-level tmp_install dir. 2015-05-13 18:48:05 -04:00
HISTORY Improve text of stub HISTORY file. 2014-02-12 18:16:17 -05:00
Makefile Allow make check in PL directories 2011-02-15 06:52:12 +02:00
README Don't generate plain-text HISTORY and src/test/regress/README anymore. 2014-02-10 20:48:04 -05:00
README.git Don't generate plain-text HISTORY and src/test/regress/README anymore. 2014-02-10 20:48:04 -05:00

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:

	http://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
http://www.postgresql.org/download/.  For more information look at our
web site located at http://www.postgresql.org/.