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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: reads are slow
Date Tue, 23 Feb 2010 18:07:22 GMT
you enable row caching by upgrading to 0.6. :)

it would help, yes, but for really big rows like yours it's probably
not a silver bullet either.

On Tue, Feb 23, 2010 at 12:04 PM, kevin <kevincastiglione@gmail.com> wrote:
> 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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