From owner-freebsd-scsi Wed Jun 12 17:19:48 2002 Delivered-To: freebsd-scsi@freebsd.org Received: from srv1.cosmo-project.de (srv1.cosmo-project.de [213.83.6.106]) by hub.freebsd.org (Postfix) with ESMTP id F0C8437B409 for ; Wed, 12 Jun 2002 17:19:44 -0700 (PDT) Received: from cicely5.cicely.de (cicely5.cicely.de [IPv6:3ffe:400:8d0:301:200:92ff:fe9b:20e7]) (authenticated bits=0) by srv1.cosmo-project.de (8.12.3/8.12.3) with ESMTP id g5D0JZSm048589 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=OK); Thu, 13 Jun 2002 02:19:38 +0200 (CEST) (envelope-from ticso@cicely5.cicely.de) Received: from cicely5.cicely.de (localhost [IPv6:::1]) by cicely5.cicely.de (8.12.1/8.12.1) with ESMTP id g5D0JjFJ082994 (version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO); Thu, 13 Jun 2002 02:19:45 +0200 (CEST)?g (envelope-from ticso@cicely5.cicely.de) Received: (from ticso@localhost) by cicely5.cicely.de (8.12.1/8.12.1/Submit) id g5D0JjGn082993; Thu, 13 Jun 2002 02:19:45 +0200 (CEST)?g (envelope-from ticso) Date: Thu, 13 Jun 2002 02:19:44 +0200 From: Bernd Walter To: Joerg Wunsch Cc: freebsd-scsi@FreeBSD.ORG Subject: Re: sync cache Message-ID: <20020613001944.GC80030@cicely5.cicely.de> Reply-To: ticso@cicely.de References: <3CFEC5F4.2070003@webvolution.net> <20020606110101.GU66505@cicely5.cicely.de> <200206121850.g5CIoXB26742@uriah.heep.sax.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200206121850.g5CIoXB26742@uriah.heep.sax.de> User-Agent: Mutt/1.3.26i X-Operating-System: FreeBSD cicely5.cicely.de 5.0-CURRENT i386 Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Wed, Jun 12, 2002 at 08:50:33PM +0200, Joerg Wunsch wrote: > Bernd Walter wrote: > > > Even if they do not need the command they should have implemented > > it as a nop. > > Why? > > > Possibly this command is even required in recent SCSI specs. > > Such a lousy implementation does not create trust in firmware. > > Of course, since the entire concept of `cache memory' is optional > to the SCSI block device model, the implementation of SYNCHRONIZE > CACHE is optional as well. I have read the specs. It is still optional if the device has no write cache. This is not the case for a raid controller which allows the drives behind to have write cache enabled. I strongly hope the controller in question explicitly disables it. Nevertheless I would expect it to be available on any modern device. OK - I have to revert that it can be a nop if there is nvram based cache. -- B.Walter COSMO-Project http://www.cosmo-project.de ticso@cicely.de Usergroup info@cosmo-project.de To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message