Greetings everyone,
I've been using FreeNAS for about 9 months. I built a 30TB ZFS Raid-Z2 server with 32GB of RAM. Long story short, throughout my experience I was getting all kinds of errors (system hangs, crashes) and I did not know what to do.
The system would crash under load when I was transferring files or doing a zpool scrub, etc etc etc. When I was using FreeNAS 8.x the system would just hang and I would have to physically reboot it, but under FreeNAS 9.x it would then automatically reboot itself. I did some googling and was trying to figure out how to do kernel debugging to try to solve my issue, then I came across some people discussing kernel panic issues and how it was relating to their default memory settings. Doing further research, I came across this page http://barbz.com.au/blog/?p=362 which basically walks you through how to set up your memory settings. I applied their 90%/75% suggestions to my 32GB of RAM and applied the following settings to my boot/loader.conf
vm.kmem_size="30886M"
vfs.zfs.arc_min="25739M"
vfs.zfs.arc_max="25739M"
vfs.zfs.prefetch_disable="0"
vfs.zfs.zil_disable="0"
vfs.zfs.txg.timeout="5"
vfs.zfs.vdev.max_pending="10"
vfs.zfs.vdev.min_pending="4"
vfs.zfs.write_limit_override="0"
I rebooted my FreeNAS a week ago with these settings and IT HAS NOT CRASHED SINCE. This is OUTSTANDING given that this system was crashing around 10-20 times per day.
That being said, I just wanted to toss this up here in case some less experienced people who are having this issue come across it and it helps them. I was literally dancing when I realized this was fixed. Hopefully this can make some other people dance too :)
Cheers friends.
I've been using FreeNAS for about 9 months. I built a 30TB ZFS Raid-Z2 server with 32GB of RAM. Long story short, throughout my experience I was getting all kinds of errors (system hangs, crashes) and I did not know what to do.
The system would crash under load when I was transferring files or doing a zpool scrub, etc etc etc. When I was using FreeNAS 8.x the system would just hang and I would have to physically reboot it, but under FreeNAS 9.x it would then automatically reboot itself. I did some googling and was trying to figure out how to do kernel debugging to try to solve my issue, then I came across some people discussing kernel panic issues and how it was relating to their default memory settings. Doing further research, I came across this page http://barbz.com.au/blog/?p=362 which basically walks you through how to set up your memory settings. I applied their 90%/75% suggestions to my 32GB of RAM and applied the following settings to my boot/loader.conf
vm.kmem_size="30886M"
vfs.zfs.arc_min="25739M"
vfs.zfs.arc_max="25739M"
vfs.zfs.prefetch_disable="0"
vfs.zfs.zil_disable="0"
vfs.zfs.txg.timeout="5"
vfs.zfs.vdev.max_pending="10"
vfs.zfs.vdev.min_pending="4"
vfs.zfs.write_limit_override="0"
I rebooted my FreeNAS a week ago with these settings and IT HAS NOT CRASHED SINCE. This is OUTSTANDING given that this system was crashing around 10-20 times per day.
That being said, I just wanted to toss this up here in case some less experienced people who are having this issue come across it and it helps them. I was literally dancing when I realized this was fixed. Hopefully this can make some other people dance too :)
Cheers friends.
