diff options
| author | Andres Freund <andres@anarazel.de> | 2025-03-24 18:20:18 -0400 |
|---|---|---|
| committer | Andres Freund <andres@anarazel.de> | 2025-03-24 18:20:18 -0400 |
| commit | adb5f85fa5a00d6d5759df55feb16dc22b0fc8d7 (patch) | |
| tree | a65425a8f98628242b91b032d791d7d28dc261fd /doc/src | |
| parent | 7d559c8580f722dc40f2c34573e53e33626679e0 (diff) | |
| download | postgresql-adb5f85fa5a00d6d5759df55feb16dc22b0fc8d7.tar.gz postgresql-adb5f85fa5a00d6d5759df55feb16dc22b0fc8d7.zip | |
Redefine max_files_per_process to control additionally opened files
Until now max_files_per_process=N limited each backend to open N files in
total (minus a safety factor), even if there were already more files opened in
postmaster and inherited by backends. Change max_files_per_process to control
how many additional files each process is allowed to open.
The main motivation for this is the patch to add io_method=io_uring, which
needs to open one file for each backend. Without this patch, even if
RLIMIT_NOFILE is high enough, postmaster will fail in set_max_safe_fds() if
started with a high max_connections. The cause of the failure is that, until
now, set_max_safe_fds() subtracted the already open files from
max_files_per_process.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/w6uiicyou7hzq47mbyejubtcyb2rngkkf45fk4q7inue5kfbeo@bbfad3qyubvs
Discussion: https://postgr.es/m/CAGECzQQh6VSy3KG4pN1d=h9J=D1rStFCMR+t7yh_Kwj-g87aLQ@mail.gmail.com
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/config.sgml | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index f923ca13a74..69fc93dffc4 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -2378,8 +2378,12 @@ include_dir 'conf.d' </term> <listitem> <para> - Sets the maximum number of simultaneously open files allowed to each - server subprocess. The default is one thousand files. If the kernel is enforcing + Sets the maximum number of open files each server subprocess is + allowed to open simultaneously, in addition to the files already open + in postmaster. The default is one thousand files. + </para> + <para> + If the kernel is enforcing a safe per-process limit, you don't need to worry about this setting. But on some platforms (notably, most BSD systems), the kernel will allow individual processes to open many more files than the system |