On Sep 27, 2012, at 5:15 PM, Reginald Beardsley <[email protected]> wrote:
> --- On Thu, 9/27/12, Richard Elling <[email protected]> wrote: >>> >>> zfs_scrub_delay = 100 >> >> a bit extreme, but probably ok >> >>> zfs_scan_idle = 1000 >> >> no, you'll want to make this smaller. > > OK, Thanks. > >> Weekly scrubs are a bit extreme. Is your hardware unreliable >> enough that you need >> to scrub weekly? > > No reliability problems except for a 3 TB drive scratch drive that failed. I > only discovered that when I was forced to reboot after a long power failure. > Both Sol 10 U8 and OI 151 have endured several power losses due to bad UPS > w/o a hiccup. It is not likely a scrub will detect this. scrubs are mostly good for detecting media problems and phantom writes. There are a whole bunch of other failure modes (eg spinup) that scrubs won't exercise. > This is new territory. I've never had the ability to check the disk integrity > before. So what is a sensible scrub schedule? Monthly? System runs 24x7 > unless I lose power or a particularly big thunderstorm is coming through in > which case I'll shut down and disconnect the cables. It's on a UPS, but I'm > on a hill in a bunch of tall trees, so it can get pretty dramatic. A few > days ago I lost 2 fluorescent light fixtures in my shop and Mom lost a > cordless phone. Add lightning to the list of things scrub doesn't exercise :-) The scrub interval is determined by an acceptable risk of checking for errors that scrub exercises. Scrubs will never offer 100% no-risk. -- richard -- illumos Day & ZFS Day, Oct 1-2, 2012 San Fransisco www.zfsday.com [email protected] +1-760-896-4422 _______________________________________________ OpenIndiana-discuss mailing list [email protected] http://openindiana.org/mailman/listinfo/openindiana-discuss
