Received: from localhost (maia-5.hub.org [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id 274FD9FBA2B for ; Tue, 27 Feb 2007 14:32:27 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-new, port 10024) with ESMTP id 40048-03 for ; Tue, 27 Feb 2007 14:32:16 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey-1.7.4 Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id A15F09FBA08 for ; Tue, 27 Feb 2007 14:32:22 -0400 (AST) Received: by noel.decibel.org (Postfix, from userid 1001) id 938BB56443; Tue, 27 Feb 2007 12:32:21 -0600 (CST) Received: (hashcash-sendmail, from uid 1001); Tue, 27 Feb 2007 12:32:20 -0600 Date: Tue, 27 Feb 2007 12:32:20 -0600 From: "Jim C. Nasby" To: pgsql-performance@postgresql.org Subject: [kris@obsecurity.org: Anyone interested in improving postgresql scaling?] Message-ID: <20070227183219.GG29041@decibel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Operating-System: FreeBSD 6.1-RELEASE-p10 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.13 (2006-08-11) X-Hashcash: 1:20:070227:pgsql-performance@postgresql.org::1x5mptaABJtAMRxo:00000 0000000000000000000000007lX5 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200702/328 X-Sequence-Number: 23382 Ok, looks like the FreeBSD community is interested in PostgreSQL performance, or at least enough to investigate it. Anyone here have experience hacking on FreeBSD? ----- Forwarded message from Kris Kennaway ----- X-Spam-Checker-Version: SpamAssassin 3.1.6 (2006-10-03) on noel.decibel.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=5.0 tests=AWL,BAYES_50, FORGED_RCVD_HELO,SPF_PASS autolearn=no version=3.1.6 Date: Sun, 25 Feb 2007 19:22:35 -0500 From: Kris Kennaway To: current@FreeBSD.org User-Agent: Mutt/1.4.2.2i Cc: performance@FreeBSD.org Subject: Anyone interested in improving postgresql scaling? Precedence: list Errors-To: owner-freebsd-current@freebsd.org If so, then your task is the following: Make SYSV semaphores less dumb about process wakeups. Currently whenever the semaphore state changes, all processes sleeping on the semaphore are woken, even if we only have released enough resources for one waiting process to claim. i.e. there is a thundering herd wakeup situation which destroys performance at high loads. Fixing this will involve replacing the wakeup() calls with appropriate amounts of wakeup_one(). Kris _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscribe@freebsd.org" ----- End forwarded message ----- -- Jim C. Nasby, Database Architect decibel@decibel.org Give your computer some brain candy! www.distributed.net Team #1828 Windows: "Where do you want to go today?" Linux: "Where do you want to go tomorrow?" FreeBSD: "Are you guys coming, or what?"