From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ric Wheeler Subject: Re: [RFT] major libata update Date: Wed, 17 May 2006 23:33:37 -0400 Message-ID: <446BEB11.4030703@emc.com> References: <20060515170006.GA29555@havoc.gtf.org> <4469B93E.6010201@emc.com> <4469E0DB.1040709@garzik.org> <4469EEC0.4060907@gmail.com> <446A1A21.80501@emc.com> <446A63F6.5030706@gmail.com> <446A6615.6050701@garzik.org> <446A678E.8030403@garzik.org> <446A6ECD.7080104@garzik.org> <446A734A.6020504@gmail.com> <446A7504.9000201@gmail.com> <446A88DF.5060705@emc.com> <446A7E4A.1080003@gmail.com> <446A9F13.4020907@emc.com> <446AAA33.5010800@gmail.com> <446B8F25.3040907@pobox.com> <446B8FC6.5040009@garzik.org> <446B9AA7.4000305@gmail.com> <446B9C1A.1060106@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mexforward.lss.emc.com ([168.159.213.200]:8544 "EHLO mexforward.lss.emc.com") by vger.kernel.org with ESMTP id S1751213AbWERCde (ORCPT ); Wed, 17 May 2006 22:33:34 -0400 In-Reply-To: <446B9C1A.1060106@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: Tejun Heo , Jeff Garzik , Mark Lord , linux-ide@vger.kernel.org, Jens Axboe Mark Lord wrote: > Tejun Heo wrote: > >> .. >> Right. Also, we need to snoop some passthrough commands and >> revalidate/reconfigure when configuration is explicitly changed. > > > Once the sysfs attr's actually work, I'll probably re-do my hdparm > stuff to detect use them when available, avoiding the need for libata > to snoop passthrough commands. But Jeff may (or not) want to snoop > anyway. > > As a workaround for now, Ric is using the ugly hack attached here. > > Cheers With this patch, I can get the write cache to change properly, but I still see rates that are "too fast" until I disable the queuing as well. I think that the barriers are supposed to work with NCQ enabled, but might there be a trace of the old "disable" barrier support if queuing is on left somewhere? Also, disabling the queue via setting /sys/class/scsi_disk/4\:0\:0\:0/device/queue_depth does not seem to take effect unless I unmount the file system & remount. I will poke around to see if reiserfs is disabling with queuing enabled & only reenables on a fresh mount... ric