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From kevin <kevincastigli...@gmail.com>
Subject Re: reads are slow
Date Tue, 23 Feb 2010 18:04:40 GMT
On Tue, Feb 23, 2010 at 9:51 AM, Brandon Williams <driftx@gmail.com> wrote:

> On Tue, Feb 23, 2010 at 11:33 AM, kevin <kevincastiglione@gmail.com>wrote:
>
>> I have given 10GB RAM in cassandra.in.sh.
>>         -Xmx10G \
>> i have increased KeysCachedFraction to 0.04. i have two different drives
>> for commitlog and data directoy.
>> i have about 3 million rows.
>> what can i do to improve read speed?
>> thanks a lot!
>>
>
> Since 0.5 doesn't have row caching, 10G is probably too much to give the
> JVM and is hampering the OS cache.  Try between 2-6GB instead and see if
> that helps.
>

the machine has 24GB of RAM, and about 4G used and 17G cached.
http://pastie.org/838979

do you still think reducing the 10G will help? it seems to be a little
counter-intuitive. i assumed giving JVM more RAM would help it!

what is row caching? how do i enable it?
thanks

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