postgresql

mirror of https://git.postgresql.org/git/postgresql.git synced 2024-08-23 01:00:41 +02:00

Go to file

Andres Freund 524dbc1433 Avoid superfluous work for commits during logical slot creation. Before `955a684e04` logical decoding snapshot maintenance needed to cope with transactions it might not have seen in their entirety. For such transactions we'd to assume they modified the catalog (could have happened before we were watching), and thus a new snapshot had to be built, and distributed to concurrently running transactions. That's problematic because building a new snapshot isn't that cheap , especially as the the array of committed transactions needs to be sorted. When creating a slot on a server with a lot of transactions, this could make logical slot creation infeasibly expensive. After `955a684e04` there's no need to deal with transaction that aren't guaranteed to be fully observable. That allows to avoid building snapshots for transactions that haven't modified catalog, even before reaching consistency. While this isn't necessarily a bugfix, slot creation being impossible in some production workloads, is severe enough to warrant backpatching. Author: Andres Freund, based on a quite different patch from Petr Jelinek Analyzed-By: Petr Jelinek Reviewed-By: Petr Jelinek Discussion: https://postgr.es/m/f37e975c-908f-858e-707f-058d3b1eb214@2ndquadrant.com Backpatch: 9.4-, where logical decoding has been introduced		2017-05-13 15:06:40 -07:00
config	Remove use of Jade and DSSSL	2017-04-06 22:09:11 -04:00
contrib	Fix race condition leading to hanging logical slot creation.	2017-05-13 14:21:00 -07:00
doc	Complete tab completion for DROP STATISTICS	2017-05-13 01:05:48 -03:00
src	Avoid superfluous work for commits during logical slot creation.	2017-05-13 15:06:40 -07:00
.dir-locals.el	emacs: Set indent-tabs-mode in perl-mode	2015-04-12 23:53:23 -04:00
.gitattributes	Remove contrib/tsearch2.	2017-02-13 11:06:11 -05:00
.gitignore	Allow .so minor version numbers above 9 in .gitignore.	2016-08-15 17:35:35 -04:00
aclocal.m4	ICU support	2017-03-23 15:28:48 -04:00
configure	Revert "Use pselect(2) not select(2), if available, to wait in postmaster's loop."	2017-04-24 18:29:03 -04:00
configure.in	Revert "Use pselect(2) not select(2), if available, to wait in postmaster's loop."	2017-04-24 18:29:03 -04:00
COPYRIGHT	Update copyright for 2017	2017-01-03 12:37:53 -05:00
GNUmakefile.in	Have "make coverage" recurse into contrib as well	2016-09-05 18:44:36 -03:00
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/.