Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tufot-00Abw8-6W for pgsql-hackers@arkaria.postgresql.org; Tue, 18 Mar 2025 22:53:59 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.94.2) (envelope-from ) id 1tufon-0074C1-Gw for pgsql-hackers@arkaria.postgresql.org; Tue, 18 Mar 2025 22:53:53 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1tufon-00749O-6C for pgsql-hackers@lists.postgresql.org; Tue, 18 Mar 2025 22:53:53 +0000 Received: from sss.pgh.pa.us ([68.162.161.243]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tufok-003aZR-2Q for pgsql-hackers@lists.postgresql.org; Tue, 18 Mar 2025 22:53:52 +0000 Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1]) by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 52IMrmea593801; Tue, 18 Mar 2025 18:53:48 -0400 From: Tom Lane To: Andres Freund cc: pgsql-hackers@lists.postgresql.org Subject: Re: pgsql: aio: Infrastructure for io_method=worker In-reply-to: References: Comments: In-reply-to Andres Freund message dated "Tue, 18 Mar 2025 16:01:43 -0000" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <593799.1742338428.1@sss.pgh.pa.us> Content-Transfer-Encoding: quoted-printable Date: Tue, 18 Mar 2025 18:53:48 -0400 Message-ID: <593800.1742338428@sss.pgh.pa.us> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk Andres Freund writes: > To allow the number of IO workers to be increased without a restart, we = need > to reserve PGPROC entries for the workers unconditionally. This has been > judged to be worth the cost. If it turns out to be problematic, we can > introduce a PGC_POSTMASTER GUC to control the maximum number. So I see this patch added 32 PGPROCs and hence 32 semaphores to the system's requirements. Unsurprisingly, this broke OpenBSD/NetBSD again: https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Dsawshark&dt=3D20= 25-03-18%2016%3A20%3A05 It's probably time to just abandon the idea of being able to run with only 60 semaphores. I wonder though if we ought to revert 38da05346 and/or 6d0154196 in view of that. regards, tom lane