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From Schubert Zhang <zson...@gmail.com>
Subject Re: concurrent reads
Date Tue, 13 Jul 2010 11:18:05 GMT
For read, the bottleneck is usually the disk.
Use iostat to check the utility of your disks.



On Tue, Jul 13, 2010 at 2:07 PM, Peter Schuller <peter.schuller@infidyne.com
> wrote:

> > Has anyone experimented with different settings for concurrent reads?  I
> > have set our servers to 4 ( 2 per processor core ).  I have noticed that
> > occasionally, our pending reads will get backed up and our servers don't
> > appear to be under too much load.  In fact, most of the load appears to
> be
> > from GC.  Is 3 per processor core too much?  Does it matter if it is an
> AMC
> > vs Intel processor?  How does processor clock speed or cache play into
> this
> > setting?
>
> Increase concurrency until you're able to either saturate CPU or
> saturate the disk subsystem. Note that the more disks you have, the
> more concurrency you'll need to fully utilize them.
>
> --
> / Peter Schuller
>

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