hh@bacher.at (Hannes Herret) writes
Chris Thompson wrote:
hh@bacher.at (Hannes Herret) writes [...]
it was a misinformation, there is no ndmp-backup running on sunday!! it seems to be normal, to take 10 hours to scrub 2x 19 x 36Gb-Disks.
That does seem about right, for 38 x 36GB discs on a single FCAL loop. How are they divided up into volumes and RAID groups? The syslog'd messages report on each of these as they complete, and the timings may be suggestive. You can also use "sysconfig -r" while the scrub is running, and it will tell you which RAID groups are being done and what the progress on each is. It's possible for the 2 parallel scrub processes (by default, "options raid.scrubbers" can alter it) to choose to do things in a non-optimal order, so that a single large RAID group gets scrubbed by itself at the end.
[& later]
When you say "2 x 19 x 36GB disks" is that meant to imply 19 x 36GB discs on each of the two F820s? In that case, 10 hours for a scrub sounds way too high, unless there has been a failover and one of them is struggling to scrub both sets of discs.
that means 1 scrubber per volume ? 2 volumes are scrubbed at the same time, or 1 volume is scrubbed by 2 scrubbers - e.g. 1 scrubber beginning with the first block, the other in the mid of the disk?
[& later]
yes, i mean a cluster-configuration with 19 disks on each side. i agree - i also think 10 hours are too high for 19 disks.
Scrubbing is done on a per RAID group basis. My understanding is that each scrubbing process does one RAID group at a time: with the default value of "options raid.scrubbers 2" this means that two RAID groups (which might or might not be part of the same volume) can be processed in parallel.
You still haven't told us how your discs are allocated to volumes and RAID groups. If all 19 discs are a single RAID group in a single volume (that would be larger than the default raidsize) then only one scrubbing process would be active.
Chris Thompson University of Cambridge Computing Service, Email: cet1@ucs.cam.ac.uk New Museums Site, Cambridge CB2 3QG, Phone: +44 1223 334715 United Kingdom.