From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Vier Subject: Re: write barrier patches for 2.4.21 Date: Thu, 28 Aug 2003 20:07:30 -0400 Message-ID: <20030829000730.GA9019@zero> References: <20030825170849.GA14811@mfa.kfki.hu> <20030826214624.GA410@zero> <20030827064103.GA29131@namesys.com> <20030827220337.GB4886@zero> <1062031059.5324.111.camel@tiny.suse.com> <20030828170725.GB21352@matchmail.com> Reply-To: Tom Vier Mime-Version: 1.0 Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com Content-Disposition: inline In-Reply-To: <20030828170725.GB21352@matchmail.com> List-Id: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Reiserfs List On Thu, Aug 28, 2003 at 10:07:25AM -0700, Mike Fedyk wrote: > On Wed, Aug 27, 2003 at 08:37:40PM -0400, Chris Mason wrote: > > scsi drives don't really need them because most scsi drives don't have > > write back caching on by default, and most actually listen when you turn > > the cache off. The scsi tag queuing makes good performance possible > > even without writeback caching. > > So, in essence, TCQ is exposing what is happening in the cache, and allowing > control/showing state compared to IDE's non-TCQ write cache. Do I have that > right? i'm not sure what you mean. chris is just saying tcq makes performance w/o write cache better. i WOULD like to see wb's used w/ scsi. it would be nice to be able to safely enable write cache on my drives. -- Tom Vier DSA Key ID 0xE6CB97DA