On Sat, 21 May 2011 13:16:18 +0200 Pol Hallen <raid1@xxxxxxxxxxxxxx> wrote: > Hi folks, after fail of a disk on my raid6 sw I check with dd the performance > of raid: > > dd if=/dev/zero of=degradedraid bs=1000024 count=100 > 100+0 records in > 100+0 records out > 100002400 bytes (100 MB) copied, 288.254 s, 347 kB/s > > is it correct? only 347Kb/s on a raid6 degraded? What was it when the array was not degraded? 1000024 is a rather strange block size to use. Try a power of 2 and see if it makes a difference. I would expect large sequential writes to go at much the same speed as non-degraded, but smaller or non-aligned writes could certainly go more slowly - maybe half speed at a guess. NeilBrown > > mdadm --detail /dev/md0 > /dev/md0: > Version : 0.90 > Creation Time : Mon Sep 27 14:19:15 2010 > Raid Level : raid6 > Array Size : 5860543744 (5589.05 GiB 6001.20 GB) > Used Dev Size : 1465135936 (1397.26 GiB 1500.30 GB) > Raid Devices : 6 > Total Devices : 7 > Preferred Minor : 0 > Persistence : Superblock is persistent > > Update Time : Sat May 21 13:14:43 2011 > State : active, degraded > Active Devices : 5 > Working Devices : 5 > Failed Devices : 2 > Spare Devices : 0 > > Layout : left-symmetric > Chunk Size : 64K > > UUID : 9bd6372e:e2eab1d5:d2bdc3cb:ad12f41d > Events : 0.385693 > > Number Major Minor RaidDevice State > 0 8 1 0 active sync /dev/sda1 > 1 8 17 1 active sync /dev/sdb1 > 2 0 0 2 removed > 3 8 81 3 active sync /dev/sdf1 > 4 8 65 4 active sync /dev/sde1 > 5 8 49 5 active sync /dev/sdd1 > > 6 8 145 - faulty spare > 7 8 33 - faulty spare > > thanks! > > Pol > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
