X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 019D59DC847 for ; Tue, 28 Feb 2006 13:23:52 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 67785-03 for ; Tue, 28 Feb 2006 13:23:51 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id C0ED39DC876 for ; Tue, 28 Feb 2006 13:23:50 -0400 (AST) Received: by noel.decibel.org (Postfix, from userid 1001) id 8553656467; Tue, 28 Feb 2006 11:23:35 -0600 (CST) Received: (hashcash-sendmail, from uid 1001); Tue, 28 Feb 2006 11:23:34 -0600 Date: Tue, 28 Feb 2006 11:23:34 -0600 From: "Jim C. Nasby" To: Javier Somoza Cc: Bruce Momjian , Tino Wildenhain , pgsql-performance@postgresql.org Subject: Re: fsync and battery-backed caches Message-ID: <20060228172334.GV82012@pervasive.com> References: <200602280106.k1S16DK16068@candle.pha.pa.us> <1141114775.1555.7.camel@pndsoft> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1141114775.1555.7.camel@pndsoft> X-Operating-System: FreeBSD 6.0-RELEASE-p4 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.11 X-Hashcash: 1:20:060228:jsomoza@pandasoftware.es::rN9zQXol/y+JVsv0:0000000000000 0000000000000000000000003yOg X-Hashcash: 1:20:060228:pgman@candle.pha.pa.us::/1ARJvwQ7c9qtW8y:000000000000000 0000000000000000000000004hEP X-Hashcash: 1:20:060228:tino@wildenhain.de::dIStB0nu5qwMTS3u:0000000000000000000 00000000000000000000000032aR X-Hashcash: 1:20:060228:pgsql-performance@postgresql.org::6vE8B2EeR2ytWbtW:00000 00000000000000000000000033fd X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=1.355 required=5 tests=[AWL=-1.145, RAZOR2_CF_RANGE_51_100=0.5, RAZOR2_CF_RANGE_E8_51_100=1.5, RAZOR2_CHECK=0.5] X-Spam-Score: 1.355 X-Spam-Level: * X-Archive-Number: 200602/436 X-Sequence-Number: 17422 Actually, you can't assume that a BBU means you can safely disable full-page-writes. Depending on the controller, it's still possible to end up with partially written pages. BTW, if your mailer makes doing so convenient, it would be nice to trim down your .signature; note that it's about 3x longer than the email you actually sent. On Tue, Feb 28, 2006 at 09:19:36AM +0100, Javier Somoza wrote: > > Yeah, i saw it. It says full-page-writes can be disabled > without problems. > But i wanted to confirm fsync cannot be disabled although i > have battery. > > Thanks!! :-) > > > > > We do mention battery-backed cache in our docs: > > > > http://www.postgresql.org/docs/8.1/static/wal.html > > > > If it is unclear, please let us know. > > Javier Somoza > Oficina de Direcci?n Estrat?gica > mailto:jsomoza@pandasoftware.es > > Panda Software > Buenos Aires, 12 > 48001 BILBAO - ESPA?A > Tel?fono: 902 24 365 4 > Fax: 94 424 46 97 > http://www.pandasoftware.es > Panda Software, una de las principales compa??as desarrolladoras de > soluciones de protecci?n contra virus e intrusos, presenta su nueva > familia de soluciones. Todos los usuarios de ordenadores, desde las > redes m?s grandes a los dom?sticos, disponen ahora de nuevos productos > con excelentes tecnolog?as de seguridad. M?s informaci?n en: > http://www.pandasoftware.es/productos > > > > ?Prot?jase ahora contra virus e intrusos! Pruebe gratis nuestros > productos en http://www.pandasoftware.es/descargas/ > > > > > > > > > -- Jim C. Nasby, Sr. Engineering Consultant jnasby@pervasive.com Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461