From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brad Campbell Subject: Re: Raid 5/10 discard support broken in 3.8.2 Date: Sun, 10 Mar 2013 12:49:53 +0800 Message-ID: <513C10F1.7070907@fnarfbargle.com> References: <513AC802.8070306@fnarfbargle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Dave Cundiff Cc: Linux MDADM Raid List-Id: linux-raid.ids On 10/03/13 03:56, Dave Cundiff wrote: > On Sat, Mar 9, 2013 at 12:26 AM, Brad Campbell > wrote: >> >> I'd be interested if you could test it against 3.7.9. >> >> I have a 6 drive RAID10. 3 Drives are on the on-board AHCI, and the other >> three are on an LSI 9240-8i (SAS2008 with mpt2sas module). >> >> TRIM is being passed down the stack as after an fstrim of the ext4 fs on the >> RAID the mismatch count goes through the roof. >> >> The 3 drives on the LSI are Intel 330 (which support deterministic read >> after trim) while the drives on the AHCI are Samsung 830 (which are *not* >> deterministic after trim). >> >> My raid is 6 drives in an n2 configuration, so three pairs of mirrors. Each >> one a Samsung and an Intel. >> > > While I set this up could you let me know what you have in the > following sys files? > > /sys/block/[mddevice]/discard_alignment > /sys/block/[mddevice]/queue/discard_granularity > /sys/block/[mddevice]/queue/discard_max_bytes > > Also what chunk size is your array set to? brad@srv:~$ cat /sys/block/md2/discard_alignment 32504832 brad@srv:~$ cat /sys/block/md2/queue/discard_granularity 33553920 brad@srv:~$ cat /sys/block/md2/queue/discard_max_bytes 65536 /dev/md2: Version : 1.2 Creation Time : Fri Nov 9 15:49:44 2012 Raid Level : raid10 Array Size : 628752000 (599.62 GiB 643.84 GB) Used Dev Size : 209584000 (199.87 GiB 214.61 GB) Raid Devices : 6 Total Devices : 6 Persistence : Superblock is persistent Intent Bitmap : Internal Update Time : Sun Mar 10 12:49:41 2013 State : active Active Devices : 6 Working Devices : 6 Failed Devices : 0 Spare Devices : 0 Layout : near=2 Chunk Size : 64K Name : unset:2 UUID : 5a6bc3c5:f37768c6:909783aa:2c3fbd28 Events : 23015 Number Major Minor RaidDevice State 0 8 2 0 active sync set-A /dev/sda2 1 65 66 1 active sync set-B /dev/sdu2 2 8 18 2 active sync set-A /dev/sdb2 3 65 34 3 active sync set-B /dev/sds2 4 8 50 4 active sync set-A /dev/sdd2 5 65 50 5 active sync set-B /dev/sdt2 Regards, Brad