pub fn raise_fd_limit()Expand description
Raise the soft RLIMIT_NOFILE limit toward TARGET_NOFILE,
clamped at the process’s hard cap. No-op when the inherited soft
limit is already at or above the target. Logs the action at
info on success and at warn when getrlimit / setrlimit fails.
Should be called once at binary startup AFTER tracing init (so the log lines land) and BEFORE any code that opens sockets / files / pipes (so the bump applies to every subsequent opener). Safe to call multiple times - the no-op branch makes repeats cheap and idempotent.