Received: from localhost (unknown [200.46.204.184]) by developer.postgresql.org (Postfix) with ESMTP id 962AD2E00AD for ; Tue, 29 Apr 2008 02:22:24 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.184]) (amavisd-maia, port 10024) with ESMTP id 30280-06 for ; Tue, 29 Apr 2008 02:22:15 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from westnet.com (westnet.com [216.187.52.2]) by developer.postgresql.org (Postfix) with ESMTP id AE6212E005E for ; Tue, 29 Apr 2008 02:08:11 -0300 (ADT) Received: from westnet.com (localhost [127.0.0.1]) by westnet.com (8.14.0/8.14.0) with ESMTP id m3T589uX004138; Tue, 29 Apr 2008 01:08:09 -0400 (EDT) Received: from localhost (gsmith@localhost) by westnet.com (8.14.0/8.13.2/Submit) with ESMTP id m3T589UM004134; Tue, 29 Apr 2008 01:08:09 -0400 (EDT) X-Authentication-Warning: westnet.com: gsmith owned process doing -bs Date: Tue, 29 Apr 2008 01:08:09 -0400 (EDT) From: Greg Smith X-X-Sender: gsmith@westnet.com To: Gauri Kanekar cc: pgsql-performance@postgresql.org Subject: Re: Replication Syatem In-Reply-To: <7e4ba9550804282155u655e3ab5o38d2e659b485530d@mail.gmail.com> Message-ID: References: <7e4ba9550804280638ie81dc23w472785c83cd38fcf@mail.gmail.com> <60wsmh64f6.fsf@dba2.int.libertyrms.com> <7e4ba9550804282155u655e3ab5o38d2e659b485530d@mail.gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=0.292 tagged_above=0 required=5 tests=AWL=-1.607, FS_REPLICA=1.179, SARE_SPEC_REPLICA=0.72 X-Spam-Level: X-Archive-Number: 200804/421 X-Sequence-Number: 29914 On Tue, 29 Apr 2008, Gauri Kanekar wrote: > Basically we have some background process which updates "table1" and we > don't want the application to make any changes to "table1" while vacuum. > Vacuum requires exclusive lock on "table1" and if any of the background or > application is ON vacuum don't kick off. VACUUM FULL needs an exclusive lock, the regular one does not in 8.1. It's one of the reasons FULL should be avoided. If you do regular VACUUM frequently enough, you shouldn't ever need to do a FULL one anyway. -- * Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD