From 8e964db585989734a5f6c1449ffb4c62e1190a6a Mon Sep 17 00:00:00 2001 From: Jelte Fennema-Nio Date: Tue, 11 Feb 2025 22:04:44 +0100 Subject: [PATCH v2 1/3] Bump pgbench soft open file limit (RLIMIT_NOFILE) to hard limit The default open file limit of 1024 is extremely low, given modern resources and kernel architectures. The reason that this hasn't changed is because doing so would break legacy programs that use the select(2) system call in hard to debug ways. So instead programs that want to opt-in to a higher open file limit are expected to bump their soft limit to their hard limit on startup. Details on this are very well explained in a blogpost by the systemd author[1]. This starts bumping pgbench its soft open file limit to the hard open file limit. This makes sure users are not told to change their ulimit, and then retry. Instead we now do that for them automatically. [1]: https://0pointer.net/blog/file-descriptor-limits.html --- src/bin/pgbench/pgbench.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c index 5e1fcf59c61..ea7bf980bea 100644 --- a/src/bin/pgbench/pgbench.c +++ b/src/bin/pgbench/pgbench.c @@ -6815,6 +6815,15 @@ main(int argc, char **argv) #ifdef HAVE_GETRLIMIT if (getrlimit(RLIMIT_NOFILE, &rlim) == -1) pg_fatal("getrlimit failed: %m"); + + /* + * Bump the soft limit to the hard limit to not run into low + * file limits. + */ + rlim.rlim_cur = rlim.rlim_max; + if (setrlimit(RLIMIT_NOFILE, &rlim) == -1) + pg_fatal("setrlimit failed: %m"); + if (rlim.rlim_cur < nclients + 3) { pg_log_error("need at least %d open files, but system limit is %ld", base-commit: fd602f29c19d4f483f54d93abe240c12219d9f51 -- 2.43.0