Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id E2C8E1337B4D for ; Sat, 25 Sep 2010 21:53:49 -0300 (ADT) 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 45966-06 for ; Sun, 26 Sep 2010 00:53:42 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by mail.postgresql.org (Postfix) with ESMTP id 5A858133729E for ; Sat, 25 Sep 2010 21:53:42 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.14.2/8.14.2) with ESMTP id o8Q0rgCn017535; Sat, 25 Sep 2010 20:53:42 -0400 (EDT) To: Mark Rostron cc: "pgsql-admin@postgresql.org" Subject: Re: xid wraparound In-reply-to: References: Comments: In-reply-to Mark Rostron message dated "Sat, 25 Sep 2010 17:41:09 -0700" Date: Sat, 25 Sep 2010 20:53:42 -0400 Message-ID: <17534.1285462422@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.91 tagged_above=-10 required=5 tests=BAYES_00=-1.9, T_RP_MATCHES_RCVD=-0.01 X-Spam-Level: X-Archive-Number: 201009/150 X-Sequence-Number: 35694 Mark Rostron writes: > When the XID wraps, at the moment it does so, unless you set > vacuum_freeze_min_age to 0 and a vacuum has just been performed, is > there not a chance that there will be some data loss? No. XID comparisons are modulo 2^31. regards, tom lane