From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Jelte Fennema-Nio <postgres@jeltef.nl>, Tomas Vondra <tomas@vondra.me>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Bump soft open file limit (RLIMIT_NOFILE) to hard limit on startup
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Mon, 17 Feb 2025 12:24:46 -0500"
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Date: Mon, 17 Feb 2025 12:40:39 -0500
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Andres Freund <andres@anarazel.de> writes:
> On 2025-02-12 22:52:52 +0100, Jelte Fennema-Nio wrote:
>> +				/*
>> +				 * 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)

> Why not do this only in the if (rlim.rlim_cur < nclients + 3) case?

+1, otherwise you're introducing a potential failure mode for nothing.
It'd take a couple extra lines to deal with the scenario where
rlim_max is still too small, but that seems fine.

> Other than this I think we should just apply this.

Agreed on the pgbench change.  I don't have an opinion yet on the
server changes.

			regards, tom lane