Received: from maia.hub.org (maia-5.hub.org [200.46.204.29]) by mail.postgresql.org (Postfix) with ESMTP id 48AD1633D5F for ; Thu, 29 Apr 2010 01:51:37 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.29]) (amavisd-maia, port 10024) with ESMTP id 92540-05 for ; Thu, 29 Apr 2010 04:51:24 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-gx0-f221.google.com (mail-gx0-f221.google.com [209.85.217.221]) by mail.postgresql.org (Postfix) with ESMTP id 32091633CA8 for ; Thu, 29 Apr 2010 01:51:24 -0300 (ADT) Received: by gxk21 with SMTP id 21so2662833gxk.14 for ; Wed, 28 Apr 2010 21:51:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=Z0KJQhfnHsypdxc41y6FunLRbSifeE6e+jcv3ypmZfU=; b=kMo6zBRqRnqwOu6k3lxkuD8KnVY5A0uaGQi5JkEEazGHKYsYwZc10wfrQ31Hq765ET aonLs69tdpRR3fkJVO4s4/wawo2LHfbPwT98XQIMDtzD+tUePa34W8LWXqfJu046tqw7 e71ntK1AY9D2CLZLmluZe5+0RUoBq6aIiWqhQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=nGEEFy0rpHqMDPT/xGXbqDhCj1bgdCxuB5HZIyMt/178MMt7xxg4FUQLzQwnBM9Cjc 6JOkf0S5OKp8oY4TzwtdARaA6EA3bPrkwkcyFzFWZ0L9OthepbHGEvP1iMad3jcDxdFD P7/O84wTnhzK0vlJAA3eTRlMVvE2fxO7gZIdE= MIME-Version: 1.0 Received: by 10.150.48.9 with SMTP id v9mr98199ybv.288.1272516682548; Wed, 28 Apr 2010 21:51:22 -0700 (PDT) Received: by 10.150.134.20 with HTTP; Wed, 28 Apr 2010 21:51:22 -0700 (PDT) In-Reply-To: References: <4BD8DCEA.2020003@2ndquadrant.com> Date: Wed, 28 Apr 2010 22:51:22 -0600 Message-ID: Subject: Re: more 10K disks or less 15K disks From: Scott Marlowe To: Anj Adu Cc: Greg Smith , pgsql-admin@postgresql.org Content-Type: text/plain; charset=ISO-8859-1 X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-0.949 tagged_above=-10 required=5 tests=AWL=0.950, BAYES_00=-1.9, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001 X-Spam-Level: X-Archive-Number: 201004/347 X-Sequence-Number: 34441 On Wed, Apr 28, 2010 at 10:45 PM, Anj Adu wrote: > Thanks Greg > > We do not archive the WALs. We use application-level replication to > achieve redundancy. WAL archiving was difficult to support with the > earlier hardware we had ( 6x300G 10K disks Dell 2850) given the > volumes we were dealing with. The RAID card should be from the same > manufacturer (LSI in Dell's case). I don't think Greg was talking of WAL archiving, but more of where are the WAL files and how much IO throughput the WAL needs compared to the regular old /data/base store.