Received: from maia.hub.org (unknown [200.46.204.183]) by mail.postgresql.org (Postfix) with ESMTP id C8E416336CB for ; Tue, 10 Nov 2009 11:54:00 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 78787-09 for ; Tue, 10 Nov 2009 15:53:52 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-fx0-f227.google.com (mail-fx0-f227.google.com [209.85.220.227]) by mail.postgresql.org (Postfix) with ESMTP id 4F18E6328B3 for ; Tue, 10 Nov 2009 11:53:52 -0400 (AST) Received: by fxm27 with SMTP id 27so164195fxm.3 for ; Tue, 10 Nov 2009 07:53:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=b4T9Sptc+V91rgfkn+vwIsVFfs7E6F9UW3q15XQJPlM=; b=cwMmyHM8QNdi7hxq/vAZZUn1WTVU8pCu6M0FIaPDNgfhItSBRjegWm47twyiw/USte rglLs0hP9DxjJ7ECyR88HQsO3/XjnG8haZIg5yzEn3NgHW1m85J6gzKKod0s/RckWhlK oVI56uF047sj1x/NA3024yTtiK3HGH6B99kZg= 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:content-transfer-encoding; b=cnl3W1/hFa6C1IaiwqlfZ3Q3Io67In/4F/mKCxQDm5qfZqrAJxumN1hGSdjn/1Vytg 48fnfwIgaLe4t7EuEB1vQScwz8PLBhT3SrL/I3wNvNl9F1SN9fS3ZUN+cBS5rF17NWVQ 0avhNuGxG8eqlHOgBWHrx3zAJ4O2SzWCT2UqM= MIME-Version: 1.0 Received: by 10.216.86.135 with SMTP id w7mr68820wee.176.1257868429802; Tue, 10 Nov 2009 07:53:49 -0800 (PST) In-Reply-To: <4AF936F3020000250002C4F7@gw.wicourts.gov> References: <8a1bfe660911100355l34a557ffj8244079c1fb689b5@mail.gmail.com> <8a1bfe660911100700l2a44f638m97ea6136b65deb21@mail.gmail.com> <8a1bfe660911100729q42ac732cga9bbadd52e2533dd@mail.gmail.com> <4AF936F3020000250002C4F7@gw.wicourts.gov> Date: Tue, 10 Nov 2009 16:53:49 +0100 Message-ID: <8a1bfe660911100753nef2879by2c4f0b2215bf8f96@mail.gmail.com> Subject: Re: limiting performance impact of wal archiving. From: Laurent Laborde To: Kevin Grittner Cc: Ivan Voras , pgsql-performance@postgresql.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.599 tagged_above=-10 required=5 tests=BAYES_00=-2.599 X-Spam-Level: X-Archive-Number: 200911/105 X-Sequence-Number: 36273 On Tue, Nov 10, 2009 at 4:48 PM, Kevin Grittner wrote: > Laurent Laborde wrote: > >> BTW, if you have any idea to improve IO performance, i'll happily >> read it. =A0We're 100% IO bound. > > At the risk of stating the obvious, you want to make sure you have > high quality RAID adapters with large battery backed cache configured > to write-back. Not sure how "high quality" the 3ware is. /c0 Driver Version =3D 2.26.08.004-2.6.18 /c0 Model =3D 9690SA-8I /c0 Available Memory =3D 448MB /c0 Firmware Version =3D FH9X 4.04.00.002 /c0 Bios Version =3D BE9X 4.01.00.010 /c0 Boot Loader Version =3D BL9X 3.08.00.001 /c0 Serial Number =3D L340501A7360026 /c0 PCB Version =3D Rev 041 /c0 PCHIP Version =3D 2.00 /c0 ACHIP Version =3D 1501290C /c0 Controller Phys =3D 8 /c0 Connections =3D 8 of 128 /c0 Drives =3D 8 of 128 /c0 Units =3D 3 of 128 /c0 Active Drives =3D 8 of 128 /c0 Active Units =3D 3 of 32 /c0 Max Drives Per Unit =3D 32 /c0 Total Optimal Units =3D 2 /c0 Not Optimal Units =3D 1 /c0 Disk Spinup Policy =3D 1 /c0 Spinup Stagger Time Policy (sec) =3D 1 /c0 Auto-Carving Policy =3D off /c0 Auto-Carving Size =3D 2048 GB /c0 Auto-Rebuild Policy =3D on /c0 Controller Bus Type =3D PCIe /c0 Controller Bus Width =3D 8 lanes /c0 Controller Bus Speed =3D 2.5 Gbps/lane > If you haven't already done so, you might want to try > elevator=3Ddeadline. That's what we use. Also tried "noop" scheduler without signifiant performance change. --=20 ker2x