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Subject: Re: Slow on heavy I/O operations.
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Roman Gorohov. wrote:

> But what I can't understand - why such non-critical(as it seems to me) disk activity,
> cause 100% busyness for disk? Its claim to be 40.000MB/s transfers, but
> sometimes its 100% busy when iostat show only 1 MB/s.

Because disk seeks count. If you have a lot of small transactions that
need seeks they'll kill performance (try running "find /" - you'll get
~500 kB/s rate and 100% busy disks).