Mirror of the official PostgreSQL GIT repository. Note that this is just a *mirror* - we don't work with pull requests on github. To contribute, please see https://wiki.postgresql.org/wiki/Submitting_a_Patch
Go to file
Melanie Plageman ff79b5b2ab Increase default effective_io_concurrency to 16
The default effective_io_concurrency has been 1 since it was introduced
in b7b8f0b609. Referencing the associated discussion [1], it
seems 1 was chosen as a conservative value that seemed unlikely to cause
regressions.

Experimentation on high latency cloud storage as well as fast, local
nvme storage (see Discussion link) shows that even slightly higher
values improve query timings substantially. 1 actually performs worse
than 0 [2]. With effective_io_concurrency 1, we are not prefetching
enough to avoid I/O stalls, but we are issuing extra syscalls.

The new default is 16, which should be more appropriate for common
hardware while still avoiding flooding low IOPs devices with I/O
requests.

[1] https://www.postgresql.org/message-id/flat/FDDBA24E-FF4D-4654-BA75-692B3BA71B97%40enterprisedb.com
[2] https://www.postgresql.org/message-id/CAAKRu_Zv08Cic%3DqdCfzrQabpEXGrd9Z9UOW5svEVkCM6%3DFXA9g%40mail.gmail.com

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAAKRu_Z%2BJa-mwXebOoOERMMUMvJeRhzTjad4dSThxG0JLXESxw%40mail.gmail.com
2025-03-12 15:57:44 -04:00
.github Add CODE_OF_CONDUCT.md, CONTRIBUTING.md, and SECURITY.md. 2024-07-02 13:03:58 -05:00
config Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
contrib pg_logicalinspect: Fix possible crash when passing a directory path. 2025-03-11 09:56:40 -07:00
doc Increase default effective_io_concurrency to 16 2025-03-12 15:57:44 -04:00
src Increase default effective_io_concurrency to 16 2025-03-12 15:57:44 -04:00
.cirrus.star Remove duplicate words in docs and code comments. 2023-10-09 09:18:47 +05:30
.cirrus.tasks.yml ci: Remove installation of libcurl 2025-03-05 22:12:20 +01:00
.cirrus.yml ci: Test NetBSD and OpenBSD 2025-02-12 09:40:07 -05:00
.dir-locals.el Make Emacs perl-mode indent more like perltidy. 2019-01-13 11:32:31 -08:00
.editorconfig Add script to keep .editorconfig in sync with .gitattributes 2025-02-01 10:09:45 +01:00
.git-blame-ignore-revs Add commit 76aa615943 to .git-blame-ignore-revs 2025-02-01 16:48:18 +09:00
.gitattributes Add script to keep .editorconfig in sync with .gitattributes 2025-02-01 10:09:45 +01:00
.gitignore Update top-level .gitignore. 2022-12-04 15:23:00 -05:00
.mailmap Add a Git .mailmap file 2024-11-05 13:56:02 +01:00
aclocal.m4 autoconf: Move export_dynamic determination to configure 2022-12-06 18:55:28 -08:00
configure Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
configure.ac Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
COPYRIGHT Update copyright for 2025 2025-01-01 11:21:55 -05:00
GNUmakefile.in Allow selecting the git revision to be packaged by "make dist". 2024-05-03 11:08:50 -04:00
HISTORY Canonicalize some URLs 2020-02-10 20:47:50 +01:00
Makefile Remove AIX support 2024-02-28 15:17:23 +04:00
meson_options.txt Add support for OAUTHBEARER SASL mechanism 2025-02-20 16:25:17 +01:00
meson.build Make test portlock logic work with meson 2025-02-21 11:25:05 -05:00
README.md Revise the style of a paragraph in README.md. 2024-03-21 10:16:41 -05:00

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.

Copyright and license information can be found in the file COPYRIGHT.

General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.

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