From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sevrin Robstad Subject: Re: bad performance on RAID 5 Date: Thu, 18 Jan 2007 19:19:42 +0100 Message-ID: <45AFBA3E.9070000@start.no> References: <45AE9640.1040500@start.no> <45AEA550.5070005@lucidpixels.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7BIT Return-path: In-reply-to: <45AEA550.5070005@lucidpixels.com> Sender: linux-raid-owner@vger.kernel.org To: Justin Piszcz Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Justin Piszcz wrote: >> I'm suffering from bad performance on my RAID5. >> >> a "echo check >/sys/block/md0/md/sync_action" >> >> gives a speed at only about 5000K/sec , and HIGH load average : >> >> # uptime >> 20:03:55 up 8 days, 19:55, 1 user, load average: 11.70, 4.04, 1.52 >> >> kernel is 2.6.18.1.2257.fc5 >> mdadm is v2.5.5 >> >> the system consist of an athlon XP1,2GHz and two Sil3114 4port S-ATA >> PCI cards with a total of 6 250gb S-ATA drives connected. >> >> [root@compaq ~]# mdadm --detail /dev/md0 >> /dev/md0: >> Version : 00.90.03 >> Creation Time : Tue Dec 5 00:33:01 2006 >> Raid Level : raid5 >> Array Size : 1218931200 (1162.46 GiB 1248.19 GB) >> Device Size : 243786240 (232.49 GiB 249.64 GB) >> Raid Devices : 6 >> Total Devices : 6 >> Preferred Minor : 0 >> Persistence : Superblock is persistent >> >> Update Time : Wed Jan 17 23:14:39 2007 >> State : clean >> Active Devices : 6 >> Working Devices : 6 >> Failed Devices : 0 >> Spare Devices : 0 >> >> Layout : left-symmetric >> Chunk Size : 256K >> >> UUID : 27dce477:6f45d11b:77377d08:732fa0e6 >> Events : 0.58 >> >> Number Major Minor RaidDevice State >> 0 8 1 0 active sync /dev/sda1 >> 1 8 17 1 active sync /dev/sdb1 >> 2 8 33 2 active sync /dev/sdc1 >> 3 8 49 3 active sync /dev/sdd1 >> 4 8 65 4 active sync /dev/sde1 >> 5 8 81 5 active sync /dev/sdf1 >> [root@compaq ~]# >> >> >> Sevrin >> - >> To unsubscribe from this list: send the line "unsubscribe linux-raid" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > If they are on the PCI bus, that is about right, you probably should > be getting 10-15MB/s, but it is about right. If you had each drive on > its own PCI-e controller, then you would get much faster speeds. > > There are two controllers, 4 disks connected to one controller on the PCI-bus and 2 disks connected to the other controller. As you say I should have had 10-15MB/s, but I'm having 5MB *and* with really high load average. Sevrin