From owner-freebsd-database@FreeBSD.ORG Sun Mar 18 11:51:44 2007 Return-Path: X-Original-To: freebsd-database@freebsd.org Delivered-To: freebsd-database@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id D907616A401; Sun, 18 Mar 2007 11:51:44 +0000 (UTC) (envelope-from Axel.Rau@Chaos1.DE) Received: from mail1.chaos1.de (Mail1.Chaos1.de [213.160.12.53]) by mx1.freebsd.org (Postfix) with ESMTP id 97BB213C4C9; Sun, 18 Mar 2007 11:51:44 +0000 (UTC) (envelope-from Axel.Rau@Chaos1.DE) Received: from claudius6.in.chaos1.de ([192.168.220.106]) by mail1.chaos1.de with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.44) id 1HStvL-0007lH-4N; Sun, 18 Mar 2007 12:51:43 +0100 Mime-Version: 1.0 (Apple Message framework v752.2) In-Reply-To: <111EFCD1-0B88-4646-BCF5-B13D1F3BBCB0@khera.org> References: <8CDBEAF9-0945-4CD2-89C4-58AA63850ECC@Chaos1.DE> <111EFCD1-0B88-4646-BCF5-B13D1F3BBCB0@khera.org> Content-Type: text/plain; charset=UTF-8; delsp=yes; format=flowed Message-Id: <7489C7AA-BD33-4144-ABD4-73338CD5C7C7@Chaos1.DE> Content-Transfer-Encoding: quoted-printable From: Axel Rau Date: Sun, 18 Mar 2007 12:51:17 +0100 To: freebsd-database@freebsd.org, FreeBSD AMD list X-Mailer: Apple Mail (2.752.2) Cc: Subject: Re: New Opteron box, dedicated to PostgreSQL X-BeenThere: freebsd-database@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Database use and development under FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 18 Mar 2007 11:51:44 -0000 Am 16.03.2007 um 21:04 schrieb Vivek Khera: > > On Mar 16, 2007, at 7:17 AM, Claus Guttesen wrote: > >>> while configuring my 1st PostgreSQL box with dual Opterons (2212) on >>> FreeBSD, I have some questions: >>> >>> 3. What are the recommendations for tuning I/O)? >>> - setting sysctl vfs.read_max to 16 or 32 >>> - rebuilding the relevant filesystem with 32K blocks and 4K =20 >>> frags >>> Are these reliable? >> >> The following were suggetions from Vivek Khera: > > I've recently bumped the shmall and shmmax on my dual opteron with =20 > 16GB of RAM, and increased correspondingly the shared buffers. > > The max shmall you can set on freebsd (at least 6.1) is 2147483647, =20= > so I set shmall to 524288 to correspond. This supports 250000 =20 > shared buffers and 100 max connections. Might support more, but =20 > definitely not 260000. This box will start with 8GB of RAM, should also support 100 =20 connections, so I will try half of your values (pretty your settings =20 posted by Claus Guttesen ). > > I'm also using vfs.read_max=3D32 but I haven't really tested if it =20 > makes a big difference in formal benchmarks. > > The other day I was having some I/O overload, so I tried setting =20 > vfs.hirunningspace to 3K but it didn't solve my immediate problem. =20= > I've left that setting for now. Doesn't seem to really make a big =20 > difference. > > I find that the adaptec 2230SLP RAID controllers are not able to =20 > keep up with my load, but the LSI 320-2X is. I'm currently =20 > investigating external arrays attached via fibre for some boost. This box will have an Areca ARC-1261ML (RAID 1 for OS and WAL, RAID 0 =20= with 7xRAID1 for pg_data). Any hints beside the usual partition alignment and stripe size of =20 128kB ? Do you use ufs2 with softupdates? regards, Axel --------------------------------------------------------------------- Axel Rau, =E2=98=80Frankfurt , Germany +49 69 9514 = 18 0