From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: raid0 vs. mkfs Date: Mon, 28 Nov 2016 09:33:41 +0200 Message-ID: <8ee321ba-0576-27a6-079a-e4a4fdf0360b@scylladb.com> References: <56c83c4e-d451-07e5-88e2-40b085d8681c@scylladb.com> <9ce71838-0a1d-e4d8-5786-9ab0422688af@scylladb.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <9ce71838-0a1d-e4d8-5786-9ab0422688af@scylladb.com> Sender: linux-raid-owner@vger.kernel.org To: Chris Murphy Cc: Linux-RAID List-Id: linux-raid.ids On 11/28/2016 09:28 AM, Avi Kivity wrote: > 259,1 10 1140 0.380238333 4801 I D 3238079488 + 1024 > [mkfs.xfs] > 259,1 10 1141 0.380252580 2307 D D 3238079488 + 1024 > [kworker/10:1H] > 259,1 2 173 0.380260605 0 C D 3218709504 + 1024 [0] > 259,1 10 1142 0.380283800 4801 Q D 3238080512 + 1024 > [mkfs.xfs] > 259,1 10 1143 0.380284158 4801 G D 3238080512 + 1024 > [mkfs.xfs] > 259,1 10 1144 0.380285150 4801 I D 3238080512 + 1024 > [mkfs.xfs] > 259,1 10 1145 0.380297127 2307 D D 3238080512 + 1024 > [kworker/10:1H] > 259,1 10 1146 0.380324340 4801 Q D 3238081536 + 1024 > [mkfs.xfs] > 259,1 10 1147 0.380324648 4801 G D 3238081536 + 1024 > [mkfs.xfs] > 259,1 10 1148 0.380325663 4801 I D 3238081536 + 1024 > [mkfs.xfs] > 259,1 2 174 0.380328083 0 C D 3218710528 + 1024 [0] > > > So we see these one-megabyte requests; moreover, they are issued > sequentially. > Correction, they are issued in parallel, but not merged. The "C" entries correspond to requests issued far in the past.