Hi all, I am experiencing hard lockup when running 8.1-RELEASE amd64. The last two times it has happened I was running a zpool scrub (high cpu and io load). /var/log/messages has some errors looking like: kernel: ad0: FAILURE - READ_DMA4 but these didn't seem to correspond to the exact time of the lockup. any suggestions? Thanks, Greg
On Sun, Feb 06, 2011 at 01:01:14PM -0800, Greg Bonett wrote:> Hi all, > I am experiencing hard lockup when running 8.1-RELEASE amd64. The last > two times it has happened I was running a zpool scrub (high cpu and io > load). /var/log/messages has some errors looking like: > kernel: ad0: FAILURE - READ_DMA4 > > but these didn't seem to correspond to the exact time of the lockup. > > any suggestions?Given that you're running 8.1-RELEASE, what sort of ZFS tunings are you using in /boot/loader.conf? Tuning is required on this version. The ad0 READ_DMA48 errors could indicate you have a hard disk with bad blocks or is going bad in a different manner. Please install ports/sysutils/smartmontools and provide output of "smartctl -a /dev/ad0" here and I can help you determine that. -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP 4BD6C0CB |
On Tue, Feb 22, 2011 at 11:05:00AM +0000, Bruce Cran wrote:> On Mon, 2011-02-07 at 00:55 -0800, Jeremy Chadwick wrote: > > > # NOTE: Systems with 8GB of RAM or more have prefetch enabled by default. > > vfs.zfs.prefetch_disable="1" > > I think ZFS is enabled with 4 GB or more, not 8 GB: > > "ZFS NOTICE: Prefetch is disabled by default if less than 4GB of RAM is > present; to enable, add "vfs.zfs.prefetch_disable=0" > to /boot/loader.conf."The message ZFS on FreeBSD spits out (shown above) is somewhat inaccurate. I spent the time looking at the code and blogged about the condition over a year ago: http://koitsu.wordpress.com/2009/10/12/testing-out-freebsd-8-0-rc1/ Search for "ZFS NOTICE: system has less than 4GB" on the page above. I still feel the message needs to be re-worded, despite having gone through multiple changes of phrasing already. -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP 4BD6C0CB |