From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaohua Li Subject: Re: [patch 0/7] Add TRIM support for raid linear/0/1/10 Date: Wed, 14 Mar 2012 19:14:30 +0800 Message-ID: References: <20120312030412.375458948@fusionio.com> <4F5EFEB6.4060402@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Holger Kiehl Cc: "linux-kernel@vger.kernel.org" , "linux-raid@vger.kernel.org" , "neilb@suse.de" , "axboe@kernel.dk" List-Id: linux-raid.ids 2012/3/14 Holger Kiehl : > On Wed, 14 Mar 2012, Shaohua Li wrote: > >> 2012/3/13 Holger Kiehl : >>> >>> On Tue, 13 Mar 2012, Shaohua Li wrote: >>> >>>> Thanks for testing. This is very wield, the req->__data_len is wro= ng. >>>> Is this a clean build? >>>> >>> I just downloaded linux-3.3-rc7.tar.bz2 from kernel.org and applied >>> your patches again. The result is the same. >>> >>> Am I the only one experiencing these problems? >> >> Martin Petersen pointed out scsi layer doesn't support discard merge= , >> which >> might be the reason you see the error message (my drive isn't a scsi >> device). >> can you please try attached patch? >> > Thanks! After this patch the error messages are away. > > However, when the system boots it takes a very long time to boot: > > =A0 [ =A0 16.527389] EXT4-fs (md0): mounted filesystem with ordered d= ata mode. > Opts: discard,commit=3D2400,journal_async_commit > =A0 [ =A0 24.218410] EXT4-fs (md2): mounted filesystem with ordered d= ata mode. > Opts: discard,commit=3D600,journal_async_commit > =A0 [ =A0 69.823138] udevd[474]: timeout '/sbin/blkid -o udev -p /dev= /md0' > =A0 [ =A0 70.824197] udevd[474]: timeout: killing '/sbin/blkid -o ude= v -p > /dev/md0' [866] > =A0 [ =A0 70.826823] udevd[474]: '/sbin/blkid -o udev -p /dev/md0' [8= 66] > terminated by signal 9 (Killed) > =A0 [ =A0 70.829290] udevd[474]: timeout 'udisks-part-id /dev/md0' > =A0 [ =A0 74.942625] udevd[475]: timeout '/sbin/blkid -o udev -p /dev= /md2' > =A0 [ =A0 75.947158] udevd[475]: timeout: killing '/sbin/blkid -o ude= v -p > /dev/md2' [874] > =A0 [ =A0 75.949734] udevd[475]: '/sbin/blkid -o udev -p /dev/md2' [8= 74] > terminated by signal 9 (Killed) > =A0 [ =A0 75.951945] udevd[475]: timeout 'udisks-part-id /dev/md2' > =A0 [ =A0 79.023741] rmmod[886]: ERROR: Module scsi_wait_scan does no= t exist in > /proc/modules > =A0 [ =A0 96.005919] systemd[1]: dev-md3.swap activation timed out. S= topping. > =A0 [ =A0127.292002] Adding 9434108k swap on /dev/md3. =A0Priority:0 = extents:1 > across:9434108k > > During another boot I saw this additional message: > > =A0 [ =A0 11.988732] scsi_verify_blk_ioctl: 930 callbacks suppressed > > The strange thing is that after boot I tried to enter the command > '/sbin/blkid -o udev -p /dev/md0' and it works without any problems > (time for this is 0m0.001s). So I also tried booting without discard > option, but the result is the same. > > Otherwise I observed no problems. Even running some more extensive > benchmark testing showed no problems. Only the performance drop is > dramatic. In my own benchmark where thousand of files get copied arou= nd > via FTP the performance drops from 4000 files per second to 520 when > mounting the filesystem with discard option. Also during the benchmar= k > any access to the disk can take very very long if discard is enabled. > > Next, I will try this patch on a system without SATA/SCSI disks. Maybe the discard runs slow with small size request in the disk. please drop patch "blk: add plug for blkdev_issue_discard" and try agai= n. Since we can't do merge, the plug just introduces latency. if it doesn't help, please capture a blktrace when you do the benchmark= and send it to me. Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html