From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 9F4617F6D for ; Mon, 17 Mar 2014 17:51:04 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay3.corp.sgi.com (Postfix) with ESMTP id 3298DAC004 for ; Mon, 17 Mar 2014 15:51:03 -0700 (PDT) Received: from greer.hardwarefreak.com (mo-65-41-216-221.sta.embarqhsd.net [65.41.216.221]) by cuda.sgi.com with ESMTP id MeBIBEfoqAGPcoAp for ; Mon, 17 Mar 2014 15:51:02 -0700 (PDT) Message-ID: <53277C56.7000002@hardwarefreak.com> Date: Mon, 17 Mar 2014 17:51:02 -0500 From: Stan Hoeppner MIME-Version: 1.0 Subject: Re: elevator question References: In-Reply-To: Reply-To: stan@hardwarefreak.com List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: weber@zbfmail.de, Xfs On 3/17/2014 10:35 AM, Marko Weber|8000 wrote: > > hello list, > in the xfs faq i read elevator=noop is best when using ssd. > i have the gentoo system on a ssd, but the larger data storage partition > on softraid with some sata disks. > is elevator=noop in this combo still best? The elevator is per physical device. For SSD use noop. But with your setup is doesn't matter as md/RAID will run at rust speed. A better solution is to remove the SSD partition from the md/RAID array, reshape/shrink/rebuild the array to make it happy, whatever is necessary after removing the SSD partition. Now configure the SSD partition as bcache and enable writeback policy. This will increase the performance of the rust array to SSD level for writes, and for reads after frequently accessed data is cached in your SSD. -- Stan _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs