From owner-freebsd-fs@FreeBSD.ORG Tue Aug 28 10:00:46 2007 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 036BE16A469 for ; Tue, 28 Aug 2007 10:00:46 +0000 (UTC) (envelope-from numisemis@yahoo.com) Received: from web36613.mail.mud.yahoo.com (web36613.mail.mud.yahoo.com [209.191.85.30]) by mx1.freebsd.org (Postfix) with SMTP id ABF2513C4A3 for ; Tue, 28 Aug 2007 10:00:45 +0000 (UTC) (envelope-from numisemis@yahoo.com) Received: (qmail 79008 invoked by uid 60001); 28 Aug 2007 10:00:45 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:Date:From:Subject:To:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-ID; b=ut52lYMvZ1tg1+CngsPUOZV2hWHlPEwDHQj7B1pwQDcBUv4Gmvp1xj8dxLsqEEAG8LIBWzCgCsrlR59TMxk5S5fmmgIyx974SqXh6s5RcAZ0rQLglzCcGRfC/cvWlnDe/vi/jZ5TmXunH0rgJbJWGy+vveg/pIB2xxa+rZSxJoM=; X-YMail-OSG: EaXLYugVM1lFQrN4Yo0ogQwX4RYBow_LN4josaoZ_JjWGEcef3L4a03qM0M3gHzA00AeNLZsyxHFUj0oQHckDKu3r.0KdHGymUiF5Le.Mxui3fFlf.Gg0QR_r9UgSw-- Received: from [213.147.110.159] by web36613.mail.mud.yahoo.com via HTTP; Tue, 28 Aug 2007 03:00:44 PDT Date: Tue, 28 Aug 2007 03:00:44 -0700 (PDT) From: Simun Mikecin To: freebsd-fs@freebsd.org, pjd@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Message-ID: <937640.78988.qm@web36613.mail.mud.yahoo.com> Cc: Subject: zfs and BIO_FLUSH on amr(4) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Aug 2007 10:00:46 -0000 Using storage on amr(4) controller with zfs revealed reduced write performance. It seems that writing to zfs concludes with a BIO_FLUSH call to flush the controller cache to disk. amr(4) can have onboard cache memory with or without battery backup. Is BIO_FLUSH call really needed when amr(4) is used with onboard cache memory with a battery backup? ____________________________________________________________________________________ Park yourself in front of a world of choices in alternative vehicles. Visit the Yahoo! Auto Green Center. http://autos.yahoo.com/green_center/