From owner-freebsd-stable@FreeBSD.ORG Tue Oct 31 23:54:57 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A012D16A521 for ; Tue, 31 Oct 2006 23:54:57 +0000 (UTC) (envelope-from wb@freebie.xs4all.nl) Received: from smtp-vbr13.xs4all.nl (smtp-vbr13.xs4all.nl [194.109.24.33]) by mx1.FreeBSD.org (Postfix) with ESMTP id 691BC43D93 for ; Tue, 31 Oct 2006 23:54:33 +0000 (GMT) (envelope-from wb@freebie.xs4all.nl) Received: from freebie.xs4all.nl (freebie.xs4all.nl [213.84.32.253]) by smtp-vbr13.xs4all.nl (8.13.8/8.13.8) with ESMTP id k9VNsQTo099199; Wed, 1 Nov 2006 00:54:31 +0100 (CET) (envelope-from wb@freebie.xs4all.nl) Received: from freebie.xs4all.nl (localhost [127.0.0.1]) by freebie.xs4all.nl (8.13.8/8.13.3) with ESMTP id k9VNsQAG012237; Wed, 1 Nov 2006 00:54:26 +0100 (CET) (envelope-from wb@freebie.xs4all.nl) Received: (from wb@localhost) by freebie.xs4all.nl (8.13.8/8.13.6/Submit) id k9VNsQJn012236; Wed, 1 Nov 2006 00:54:26 +0100 (CET) (envelope-from wb) Date: Wed, 1 Nov 2006 00:54:26 +0100 From: Wilko Bulte To: Fredrik Widlund Message-ID: <20061031235425.GA12218@freebie.xs4all.nl> References: <45470D95.5020801@qbrick.com> <454718DD.8060108@qbrick.com> <45471ACC.2030604@fer.hr> <4547421D.2010206@qbrick.com> <45477FCC.9050901@qbrick.com> <4547DD7E.4030509@qbrick.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4547DD7E.4030509@qbrick.com> User-Agent: Mutt/1.5.11 X-Virus-Scanned: by XS4ALL Virus Scanner Cc: freebsd-stable@freebsd.org, Ivan Voras Subject: Re: SAS Raid - mfi driver X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 Oct 2006 23:54:57 -0000 On Wed, Nov 01, 2006 at 12:34:22AM +0100, Fredrik Widlund wrote.. > Yes, it forces writeback even when the controller has no BBU. Choosing > WBack itself will default back to WThru. It's dangerous, but I guess it > should be much less dangerous than using for example softupdates. We > have little choice until our order of BBUs get here, since the > performance degradation of wthru would make it unusable for us. At least hook the machine up to an UPS if you have one. > Ivan Voras skrev: > >Fredrik Widlund wrote: > > > >>Solved my issue with LSI 8480E without BBU. With "write: BadBBU", > >>"cache: enabled", and "io: cached", performance rose to around 200MB/s > >>from 20MB/s. > >> > > > >I don't know what "BadBBU" is, but from some Googling it seems to be a > >setting that overrides BBU detection, and enables write caching even if > >the system believes BBU is broken or missing. If true, this may be > >dangerous for data consistency. > > > >_______________________________________________ > >freebsd-stable@freebsd.org mailing list > >http://lists.freebsd.org/mailman/listinfo/freebsd-stable > >To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org" > > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org" --- end of quoted text --- -- Wilko Bulte wilko@FreeBSD.org