:-)
Can you check which IO scheduler the drives are using, try different
schedulers, and see if it makes a different.
there was [anticipatory] selected.
ORIGINAL:
tiger:~# grep . /sys/block/*/queue/scheduler
/sys/block/fd0/queue/scheduler:noop [anticipatory] deadline cfq
/sys/block/hdd/queue/scheduler:noop [anticipatory] deadline cfq
/sys/block/sda/queue/scheduler:noop [anticipatory] deadline cfq
/sys/block/sdb/queue/scheduler:noop [anticipatory] deadline cfq
NEW:
tiger:~# grep . /sys/block/*/queue/scheduler
/sys/block/fd0/queue/scheduler:noop anticipatory deadline [cfq]
/sys/block/hdd/queue/scheduler:noop anticipatory deadline [cfq]
/sys/block/sda/queue/scheduler:noop anticipatory deadline [cfq]
/sys/block/sdb/queue/scheduler:noop anticipatory deadline [cfq]
System seems to work, but I need some testing time to check that
behaviour. (Any suggestion of a testing tool to generate disk
traffic and reporting response-times and throughput?)
Which is the right way / position on bootup to set this field
permanent to this value and what exactly did I change with this
modification? (Performance issues?)
I'm using debian..
I also need to check this on the other (identical) machines.
Thanks! Miro Dietiker