Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id D68501337B2F for ; Thu, 31 Mar 2011 22:39:11 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 42543-04 for ; Fri, 1 Apr 2011 01:38:53 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from tamriel.snowman.net (tamriel.snowman.net [72.66.115.51]) by mail.postgresql.org (Postfix) with ESMTP id 17C5A1337999 for ; Thu, 31 Mar 2011 22:38:53 -0300 (ADT) Received: by tamriel.snowman.net (Postfix, from userid 1000) id 98513229A7; Thu, 31 Mar 2011 21:38:53 -0400 (EDT) Date: Thu, 31 Mar 2011 21:38:53 -0400 From: Stephen Frost To: Selva manickaraja Cc: pgsql-admin@postgresql.org Subject: Re: Too many WAL(s) despite low transaction Message-ID: <20110401013853.GC4116@tamriel.snowman.net> References: <20110401004240.GA4116@tamriel.snowman.net> <20110401010336.GB4116@tamriel.snowman.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ZkRJodCQ+mTEVfmM" Content-Disposition: inline In-Reply-To: X-Editor: Vim http://www.vim.org/ X-Info: http://www.snowman.net X-Operating-System: Linux/2.6.32-5-amd64 (x86_64) X-Uptime: 21:31:49 up 57 days, 10:01, 13 users, load average: 0.10, 0.06, 0.01 User-Agent: Mutt/1.5.20 (2009-06-14) 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: 201103/305 X-Sequence-Number: 37177 --ZkRJodCQ+mTEVfmM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Selva, * Selva manickaraja (mavles78@gmail.com) wrote: > If our check_timeout is 30 minutes, what would be an acceptable time limit > for archive_timeout? They're two different things. Checkpoints are about getting data flushed out to the data files (so they're not just in the WALs), archive_timeout is about how often WAL segments should be forcibly archived (so that the archive server doesn't end up missing data on low-write systems). Typically, I'd pick archive_timeout of around 5m or 10m, depending on how much time you don't mind losing. I'd also compress the WALs (on a low-write system, they're going to have very little data in them). There's also a utility out there, iirc, which will truncate WALs to remove empty space. > Also since bulk loading/migration of large amount of data was done earlier, > do I need to run vacuum etc. Erm, you should be running autovacuum.. Stephen --ZkRJodCQ+mTEVfmM Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAk2VLK0ACgkQrzgMPqB3kiir1wCdH1JpDxkyXVj61HbTmaOGMSh4 N04An3IrX/f6aRu8rtsh52ZJBwJssFzr =6QR2 -----END PGP SIGNATURE----- --ZkRJodCQ+mTEVfmM--