Robert Milkowski wrote:
Saturday, December 9, 2006, 7:07:49 PM, you wrote:
ek> Jim Mauro wrote:
Could be NFS synchronous semantics on file create (followed by
repeated flushing of the write cache). What kind of storage are you
using (feel free to send privately if you need to) - is it a thumper?
It's not clear why NFS-enforced synchronous semantics would induce
different behavior than the same
load to a local ZFS.
ek> Actually i forgot he had 'zil_disable' turned on, so it won't matter in
ek> this case.
Ben, are you sure zil_disable was set to 1 BEFORE pool was imported?
Yes, absolutely. Set var in /etc/system, reboot, system come up. That
happened almost 2 months ago, long before this lock insanity problem
To be clear, the ZIL issue was a problem for creation of a handful of
files of any size. Untar'ing a file was a massive performance drain.
This issue, other the other hand, deals with thousands of little files
being created all the time (IMAP Locks). These are separate issues from
my point of view. With ZIL slowness NFS performance was just slow but
we didn't see massive CPU usage, with this issue on the other hand we
were seeing waves in 10 second-ish cycles where the run queue would go
sky high with 0 idle. Please see the earlier mails for examples of the
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