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Date: Wed, 3 Jun 2009 19:48:47 -0500
Message-ID: <e06563880906031748l32a1e1ean3dac0331f347c75@mail.gmail.com>
Subject: Re: cassandra's performance?
From: Jonathan Ellis <jbellis@gmail.com>
To: cassandra-user@incubator.apache.org
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Cassandra is not designed to work memory-only.  It's designed designed
to use disk for durability and to accommodate using large sets of
data, letting the OS use memory as a huge cache for that.  For typical
data use patterns (where a relatively small amount is "hot") this will
be a much better use of hardware than memory-only.

On Wed, Jun 3, 2009 at 7:44 PM, lichun li <lilichun@gmail.com> wrote:
> Thank you!
> The "how fast is it" section says:"In a nutshell, Cassandra is much
> faster than relational databases, and much slower than memory-only
> systems or systems that don't sync each update to disk."
> Can Cassandra work in a memory-only mode? Can it be done by just
> changing configuration?
>
> On Wed, Jun 3, 2009 at 10:38 PM, Jonathan Ellis <jbellis@gmail.com> wrote=
:
>> We're basically in a roll-your-own benchmark state. =A0Johan can
>> probably give some pointers:
>> http://blog.oskarsson.nu/2009/05/vpork.html. =A0Also see the "how fast
>> is it" section here:
>> http://spyced.blogspot.com/2009/05/cassandra-03-release-candidate-and.ht=
ml
>>
>> -Jonathan
>>
>> On Wed, Jun 3, 2009 at 3:06 AM, lichun li <lilichun@gmail.com> wrote:
>>> I can't find cassandra's performance data, such as throughput. Does
>>> anyone know where to find these data?
>>>
>>> --
>>> Sincerely yours,
>>>
>>> Lichun Li
>>> Mobile Life New Media Lab, BUPT
>>>
>>
>
>
>
> --
> Sincerely yours,
>
> Lichun Li
> Mobile Life New Media Lab, BUPT
>