On Thu, 11 May 2006, dean gaudet wrote: > On Tue, 14 Mar 2006, Neil Brown wrote: > > > On Monday March 13, patrik@xxxxxxxxxxx wrote: > > > I just experienced some kind of lockup accessing my 8-drive raid5 > > > (2.6.16-rc4-mm2). The system has been up for 16 days running fine, but > > > now processes that try to read the md device hang. ps tells me they are > > > all sleeping in get_active_stripe. There is nothing in the syslog, and I > > > can read from the individual drives fine with dd. mdadm says the state > > > is "active". ... > > i seem to be running into this as well... it has happenned several times > in the past three weeks. i attached the kernel log output... it happenned again... same system as before... > > You could try increasing the size of the stripe cache > > echo 512 > /sys/block/mdX/md/stripe_cache_size > > (choose and appropriate 'X'). > > yeah that got things going again -- it took a minute or so maybe, i > wasn't paying attention as to how fast things cleared up. i tried 768 this time and it wasn't enough... 1024 did it again... > > > Maybe check the content of > > /sys/block/mdX/md/stripe_cache_active > > as well. > > next time i'll check this before i increase stripe_cache_size... it's > 0 now, but the raid5 is working again... here's a sequence of things i did... not sure if it helps: # cat /sys/block/md4/md/stripe_cache_active 435 # cat /sys/block/md4/md/stripe_cache_size 512 # echo 768 >/sys/block/md4/md/stripe_cache_size # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # cat /sys/block/md4/md/stripe_cache_active 752 # echo 1024 >/sys/block/md4/md/stripe_cache_size # cat /sys/block/md4/md/stripe_cache_active 927 # cat /sys/block/md4/md/stripe_cache_active 151 # cat /sys/block/md4/md/stripe_cache_active 66 # cat /sys/block/md4/md/stripe_cache_active 2 # cat /sys/block/md4/md/stripe_cache_active 1 # cat /sys/block/md4/md/stripe_cache_active 0 # cat /sys/block/md4/md/stripe_cache_active 3 and it's OK again... except i'm going to lower the stripe_cache_size to 256 again because i'm not sure i want to keep having to double it each freeze :) let me know if you want the task dump output from this one too. -dean - 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
