From 260acb8293b957774eae26aa0374860e28a5a71e Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Fri, 1 Dec 2017 15:34:23 +1300 Subject: [PATCH] Update documentation to mention huge pages on other OSes. Currently the docs imply that only Linux can use huge pages. That's not quite true: it's just that Linux is the only OS where we know how to request them explicitly. Author: Thomas Munro Reviewed-By: Justin Pryzby Discussion: https://postgr.es/m/CAEepm=3qzR-hfjepymohuC4XO5phxoSoipOjm6BEhnJHjNR+jg@mail.gmail.com --- doc/src/sgml/config.sgml | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 3060597011d..c104bb66217 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -1363,7 +1363,7 @@ include_dir 'conf.d' - Enables/disables the use of huge memory pages. Valid values are + Controls whether huge memory pages are requested. Valid values are try (the default), on, and off. @@ -1371,6 +1371,13 @@ include_dir 'conf.d' At present, this feature is supported only on Linux. The setting is ignored on other systems when set to try. + Note that some other operating systems including FreeBSD and Illumos + can use huge pages (also known as "super" pages or "large" pages) + automatically without an explicit request from + PostgreSQL. Linux + also has an optional "transparent huge pages" feature, but its + performance has shown to be inferior to that of explicitly requested + huge pages on some versions. -- 2.15.0