You don't need to wait. You can use the array now. But ouch 305K/sec! If this a 386-33? :) Have you tried dd tests on each disk to verify each works well? Something like: time dd if=/dev/sdc1 of=/dev/null bs=64k count=100000 This is just a read test. My disks take about 340 seconds. Yours should be about twice as fast. Each disk should give about the same performance. You may find 1 that has issues. If you are willing to re-build the array, you could do a write test: time dd if=/dev/zero of=/dev/sdc1 bs=64k count=10000 THIS WILL TRASH THE ARRAY!!! Guy -----Original Message----- From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of PAulN Sent: Thursday, August 19, 2004 1:53 PM To: Guy Cc: linux-raid@xxxxxxxxxxxxxxx Subject: Re: Raid5 Construction Question Guy, thanks for the snappy reply! I wish my disks were as fast :) I failed to mention that I had been tweaking those proc values. Currently they are: (root@lcn0:raid)# cat speed_limit_max 200000 (root@lcn0:raid)# cat speed_limit_min 10000 If I'm correct, this means that the min speed is 10MB/sec per device. I've verified that each device has a seq write speed of about 38MB/sec so each should be capable of handling 10,000Kbytes sec. Right after I issue a raidstart the speed is pretty good (~30MB/sec) but is just falls until it hits around 300K. md0 : active raid5 sdh1[7] sdf1[6] sdg1[5] sde1[4] sdd1[3] sdc1[2] sdb1[1] sda1[0] 481949184 blocks level 5, 64k chunk, algorithm 2 [7/7] [UUUUUUU] [>....................] resync = 2.4% (1936280/80324864) finish=4261.4min speed=305K/sec In the docs I saw that "reconstruction" is possible with raidhotadd but I didn't see anything about initialization. So am I "screwed" until the resync is fixed? I was depeding on the disks to do some filesystem testing but maybe I'll have to wait a few days.. Thanks, Paul Guy wrote: >In short... Issue this command: >echo 100000 > /proc/sys/dev/raid/speed_limit_max > >If it does not help issue this command and send the results: >cat /proc/mdstat > >Details below. > >These are related to throttling: >/proc/sys/dev/raid/speed_limit_max >/proc/sys/dev/raid/speed_limit_min > >Do "man md" for more info. > >The speed limits are per device, not per array. >Make sure the max is large enough the permit your disks to go as fast as >they can. I use 100000 (100,000K bytes/second). My disks are not that >fast, and having too large of a number does not hurt. >At least as a test, set the min to the same value as max. > >I use these commands when I want to change by hand: >cat /proc/sys/dev/raid/speed_limit_max >cat /proc/sys/dev/raid/speed_limit_min > >echo 100000 > /proc/sys/dev/raid/speed_limit_max >echo 1000 > /proc/sys/dev/raid/speed_limit_min > >Guy > >-----Original Message----- >From: linux-raid-owner@xxxxxxxxxxxxxxx >[mailto:linux-raid-owner@xxxxxxxxxxxxxxx] On Behalf Of PAulN >Sent: Thursday, August 19, 2004 1:25 PM >To: linux-raid@xxxxxxxxxxxxxxx >Subject: Raid5 Construction Question > >Hi, >So I have a raid 5 which is around ~1TB and the problem I've been having >is that >the resync rate is really bad. This is understandable given that the >raid5 has not >been initialized. Does anyone know a way for me to initialize my raid5 >before I use it so >that the resync process doesn't run for 3 days? >thanks >paul > > >Config: >------------------------------------------------- >raiddev /dev/md0 >raid-level 5 >nr-raid-disks 7 >nr-spare-disks 1 >chunk-size 64k >persistent-superblock 1 >parity-algorithm left-symmetric > device /dev/sda1 > raid-disk 0 > device /dev/sdb1 > raid-disk 1 > device /dev/sdc1 > raid-disk 2 > device /dev/sdd1 > raid-disk 3 > device /dev/sde1 > raid-disk 4 > device /dev/sdg1 > raid-disk 5 > device /dev/sdf1 > raid-disk 6 > device /dev/sdh1 > spare-disk 0 >---------------------------------------- > >- >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 - 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
