From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaohua Li Subject: Re: raid5-cache I/O path improvements Date: Tue, 8 Sep 2015 10:07:36 -0700 Message-ID: <20150908170736.GA423191@devbig257.prn2.facebook.com> References: <1441603250-5119-1-git-send-email-hch@lst.de> <20150908002840.GA3196542@devbig257.prn2.facebook.com> <20150908061215.GA23833@lst.de> <20150908165611.GA371379@devbig257.prn2.facebook.com> <20150908170226.GI13749@mtj.duckdns.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:4099 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754521AbbIHRHz (ORCPT ); Tue, 8 Sep 2015 13:07:55 -0400 Content-Disposition: inline In-Reply-To: <20150908170226.GI13749@mtj.duckdns.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Christoph Hellwig , neilb@suse.de, linux-raid@vger.kernel.org, Kernel-team@fb.com, dan.j.williams@intel.com, "Martin K. Petersen" , linux-ide@vger.kernel.org On Tue, Sep 08, 2015 at 01:02:26PM -0400, Tejun Heo wrote: > Hello, > > On Tue, Sep 08, 2015 at 09:56:22AM -0700, Shaohua Li wrote: > > I'll benchmark on a SSD from another vendor, which supports FUA, but FUA > > write has poor performance in my last test. > > lolwut? Was it slower than write + flush? I need double confirm. But for write + flush, we aggregrate several writes and do a flush; for FUA, we do every meta write with FUA. So this is not apple to apple comparison. Thanks, Shaohua