X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 0B40552923 for ; Wed, 1 Jun 2005 13:19:50 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 31559-05 for ; Wed, 1 Jun 2005 16:19:43 +0000 (GMT) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by svr1.postgresql.org (Postfix) with ESMTP id 7938E52943 for ; Wed, 1 Jun 2005 13:19:41 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.1/8.13.1) with ESMTP id j51GJeV9014826; Wed, 1 Jun 2005 12:19:40 -0400 (EDT) To: KeithW@narrowpathinc.com Cc: "PostgreSQL Perform" Subject: Re: Moving pg_xlog In-reply-to: <20050601151618.M48325@narrowpathinc.com> References: <20050601151618.M48325@narrowpathinc.com> Comments: In-reply-to "Keith Worthington" message dated "Wed, 01 Jun 2005 11:31:13 -0400" Date: Wed, 01 Jun 2005 12:19:40 -0400 Message-ID: <14825.1117642780@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.006 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200506/17 X-Sequence-Number: 12655 "Keith Worthington" writes: > I have been reading about increasing PostgreSQL performance by relocating the > pg_xlog to a disk other than the one where the database resides. I have the > following pg_xlogs on my system. > /raid02/databases/pg_xlog > /raid02/rhdb_databases/pg_xlog > /raid02/databases-8.0.0/pg_xlog > /var/lib/pgsql/data/pg_xlog > I have no idea why the forth entry is there. It is in the PostgreSQL > installation directory. It's there because the RPM sets up a database under /var/lib/pgsql/data. > 1) stop the postmaster > 2) rm -rf /var/lib/pgsql/data/pg_xlog > 3) mv /raid02/databases/pg_xlog /var/lib/pgsql/data/pg_xlog > 4) ln -s /var/lib/pgsql/data/pg_xlog /raid02/databases/pg_xlog > 5) start postmaster Put the xlog anywhere BUT there!!!!!!!!! > If I can do that and place the pg_xlog in the installation directory will I > create any installation issues the next time I upgrade PostgreSQL? Oh, the installation will be just fine ... but your database will not be after the upgrade wipes out your WAL. Put the xlog under some non-system-defined directory. regards, tom lane