Messages in this thread | | | From | Al Boldi <> | Subject | Re: Eradic disk access during reads | Date | Sun, 18 Sep 2005 07:16:46 +0300 |
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Willy Tarreau wrote: > On Sat, Sep 17, 2005 at 01:32:53PM +0300, Al Boldi wrote: > > Willy Tarreau wrote: > > > On Sat, Sep 17, 2005 at 07:26:11AM +0300, Al Boldi wrote: > > > > Monitoring disk access using gkrellm, I noticed that a command like > > > > > > > > cat /dev/hda > /dev/null > > > > > > > > shows eradic disk reads ranging from 0 to 80MB/s on an otherwise > > > > idle system.
New synonym: eradic=erratic :)
> Denis' tool seems clearly more suited to analyse your problem.
The problem seems to be a multi-access collision in the queue, which forces a ~50% reduction of thruput, which recovers with another multi-access collision. Maybe?!
-- Al
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