From owner-freebsd-database@FreeBSD.ORG Thu Jan 19 01:11:17 2006 Return-Path: X-Original-To: freebsd-database@freebsd.org Delivered-To: freebsd-database@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DE60C16A41F; Thu, 19 Jan 2006 01:11:17 +0000 (GMT) (envelope-from brdavis@odin.ac.hmc.edu) Received: from odin.ac.hmc.edu (Odin.AC.HMC.Edu [134.173.32.75]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6BEB743D46; Thu, 19 Jan 2006 01:11:17 +0000 (GMT) (envelope-from brdavis@odin.ac.hmc.edu) Received: from odin.ac.hmc.edu (localhost.localdomain [127.0.0.1]) by odin.ac.hmc.edu (8.13.0/8.13.0) with ESMTP id k0J1BFfC020668; Wed, 18 Jan 2006 17:11:15 -0800 Received: (from brdavis@localhost) by odin.ac.hmc.edu (8.13.0/8.13.0/Submit) id k0J1BF6L020666; Wed, 18 Jan 2006 17:11:15 -0800 Date: Wed, 18 Jan 2006 17:11:15 -0800 From: Brooks Davis To: "Jim C. Nasby" Message-ID: <20060119011115.GA18415@odin.ac.hmc.edu> References: <787bbe1c0601140457y6de99891n86b49a728eedac94@mail.gmail.com> <20060114144202.6199.qmail@web30315.mail.mud.yahoo.com> <20060119005847.GK17896@decibel.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="sm4nu43k4a2Rpi4c" Content-Disposition: inline In-Reply-To: <20060119005847.GK17896@decibel.org> User-Agent: Mutt/1.4.1i X-Virus-Scanned: by amavisd-new X-Spam-Status: No, hits=0.0 required=8.0 tests=none autolearn=no version=2.63 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on odin.ac.hmc.edu Cc: freebsd-database@freebsd.org, freebsd-performance@freebsd.org, Arne Woerner Subject: Re: Horrible PostgreSQL performance with NFS 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: Thu, 19 Jan 2006 01:11:18 -0000 --sm4nu43k4a2Rpi4c Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jan 18, 2006 at 06:58:47PM -0600, Jim C. Nasby wrote: > On Sat, Jan 14, 2006 at 06:42:02AM -0800, Arne Woerner wrote: > > Did you do those "dd" tests with small block sizes (like 1byte: > > bs=3D1), like somebody on one of those lists suggests, too? Then we > > could see, if there is a high latency that ruins everything... >=20 > FYI, PostgreSQL does 8kB I/O by default. This can only be changed by > modifying a header file. That's definitely small in my book (certainly compared to the 1MB block size the first responder suggested), knowing that, you should definitely do dd tests with 8k blocks since that's the best performance you are likely to get. -- Brooks --=20 Any statement of the form "X is the one, true Y" is FALSE. PGP fingerprint 655D 519C 26A7 82E7 2529 9BF0 5D8E 8BE9 F238 1AD4 --sm4nu43k4a2Rpi4c Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.1 (GNU/Linux) iD8DBQFDzuczXY6L6fI4GtQRAoNCAJ0dJcbZZyxaFn3+JPvgQjYNon3+DQCfXquj il7c4HKlug5OMn5bna5E0rE= =6iId -----END PGP SIGNATURE----- --sm4nu43k4a2Rpi4c--