Received: from localhost (unknown [200.46.204.182]) by postgresql.org (Postfix) with ESMTP id 47E7C9FA086 for ; Fri, 7 Sep 2007 22:48:32 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.182]) (amavisd-maia, port 10024) with ESMTP id 42041-09 for ; Fri, 7 Sep 2007 22:48:01 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from oxford.xeocode.com (unknown [87.127.95.196]) by postgresql.org (Postfix) with ESMTP id 4F0719FA0E4 for ; Fri, 7 Sep 2007 22:48:29 -0300 (ADT) Received: from localhost ([127.0.0.1] helo=oxford.xeocode.com) by oxford.xeocode.com with esmtp (Exim 4.67) (envelope-from ) id 1ITpQw-0001s5-LJ; Sat, 08 Sep 2007 02:48:26 +0100 To: "Tom Lane" Cc: Subject: Re: WIP patch for latestCompletedXid method of computing snapshot xmax In-Reply-To: <3018.1189214811@sss.pgh.pa.us> (Tom Lane's message of "Fri\, 07 Sep 2007 21\:26\:51 -0400") User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1 (gnu/linux) X-Draft-From: ("nnimap+mail01.enterprisedb.com:INBOX.patches" 2462) References: <3018.1189214811@sss.pgh.pa.us> From: Gregory Stark Organization: EnterpriseDB Date: Sat, 08 Sep 2007 02:48:26 +0100 Message-ID: <878x7i0vx1.fsf@oxford.xeocode.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200709/115 X-Sequence-Number: 3657 "Tom Lane" writes: > This patch implements Florian's idea about how to manage snapshot xmax > without the ugly and performance-losing tactic of taking XidGenLock and > ProcArrayLock at the same time. I had to do a couple of slightly klugy > things to get bootstrap and prepared transactions to work, but on the > whole it seems at least as clean as the code we have now. Comments? Just that it will be fascinating to see what effects this has on the benchmarks. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com