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From Dathan Pattishall <datha...@gmail.com>
Subject Re: what causes MESSAGE-DESERIALIZER-POOL to spike
Date Mon, 26 Jul 2010 20:18:48 GMT
Hpw does one set/get the read-concurrency? Also which read-concurrency, for
which pool? According to the threads tab in jconsole read-concurrency could
be among different pools. There are row-read-stag threads, lots of write
threads, row mutation stage etc.






On Mon, Jul 26, 2010 at 12:56 PM, Peter Schuller <
peter.schuller@infidyne.com> wrote:

> > MESSAGE-DESERIALIZER-POOL         1    682008        1818682
>
> On the (unverified by me) assumption that disk reads en up in this
> stage as Anthony indicates, and looking at the above line and the
> iostat output, makes me want to suggest that maybe the read
> concurrency is set to 1 and you need to increase it in order to fully
> utilize your disks.
>
> That said, I have no idea why you would have as many as 682 THOUSAND
> pending for that stage (but I'm not sure at what granularity these are
> scheduled so perhaps it is normal for e.g. big slicing reads? I don't
> know.).
>
> --
> / Peter Schuller
>

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