Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id 1A3F01337999 for ; Mon, 21 Feb 2011 22:41:37 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.243]) (amavisd-maia, port 10024) with ESMTP id 55092-07 for ; Tue, 22 Feb 2011 02:41:29 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from midnight-anchovy.ambulatoryclam.net (unknown [18.141.0.210]) by mail.postgresql.org (Postfix) with ESMTP id 656731336B42 for ; Mon, 21 Feb 2011 22:41:29 -0400 (AST) Received: by midnight-anchovy.ambulatoryclam.net (Postfix, from userid 1001) id 3335B4AC25; Mon, 21 Feb 2011 21:41:29 -0500 (EST) Date: Mon, 21 Feb 2011 21:41:29 -0500 From: Dan Ports To: YAMAMOTO Takashi Cc: Kevin.Grittner@wicourts.gov, heikki.linnakangas@enterprisedb.com, pgsql-hackers@postgresql.org Subject: Re: SSI bug? Message-ID: <20110222024129.GC74913@csail.mit.edu> References: <4D616C14020000250003AD9A@gw.wicourts.gov> <20110221234236.4635E19D574@mail.netbsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110221234236.4635E19D574@mail.netbsd.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.107 tagged_above=-5 required=5 tests=BAYES_00=-1.9, RDNS_NONE=0.793 X-Spam-Level: X-Archive-Number: 201102/2001 X-Sequence-Number: 182790 On Mon, Feb 21, 2011 at 11:42:36PM +0000, YAMAMOTO Takashi wrote: > i tested ede45e90dd1992bfd3e1e61ce87bad494b81f54d + ssi-multi-update-1.patch > with my application and got the following assertion failure. > > #4 0x0827977e in CheckTargetForConflictsIn (targettag=0xbfbfce78) > at predicate.c:3657 > 3657 Assert(locallock != NULL); It looks like CheckTargetForConflictsIn is making the assumption that the backend-local lock table is accurate, which was probably even true at the time it was written. Unfortunately, it hasn't been for a while, and the new changes for tuple versions make it more likely that this will actually come up. The solution is only slightly more complicated than just removing the assertion. Unless Kevin beats me to it, I'll put together a patch later tonight or tomorrow. (I'm at the airport right now.) Dan -- Dan R. K. Ports MIT CSAIL http://drkp.net/