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From Jabbar Azam <aja...@gmail.com>
Subject Re: Cassandra driver performance question...
Date Mon, 24 Jun 2013 09:26:54 GMT
Hello tony,

I couldnt reply earlier because I've been decorating over the weekend so
have been a bit busy.

Let me know what's happens.

Out of couriosity why are you using and not a cql3 native driver?

Thanks

Jabbar Azam
On 24 Jun 2013 00:32, "Tony Anecito" <adanecito@yahoo.com> wrote:

> Hi Jabbar,
>
>  I was able to get the performance issue resolved by reusing the
> connection object. It will be interesting to see what happens when I use a
> connection pool from a app server.
>
> I still think it would be a good idea to have a minimal mode for metadata.
> It is rare I use metadata.
>
> Regards,
> -Tony
>
>   *From:* Tony Anecito <adanecito@yahoo.com>
> *To:* "user@cassandra.apache.org" <user@cassandra.apache.org>; Tony
> Anecito <adanecito@yahoo.com>
> *Sent:* Friday, June 21, 2013 9:33 PM
> *Subject:* Re: Cassandra driver performance question...
>
>   Hi Jabbar,
>
> I think I know what is going on. I happened accross a change mentioned by
> the jdbc driver developers regarding metadata caching. Seems the metadata
> caching was moved from the connection object to the preparedStatement
> object. So I am wondering if the time difference I am seeing on the second
> preparedStatement object is because of the Metadata is cached then.
>
> So my question is how to test this theory? Is there a way to stop the
> metadata from coming accross from Cassandra? A 20x performance improvement
> would be nice to have.
>
> Thanks,
> -Tony
>
>   *From:* Tony Anecito <adanecito@yahoo.com>
> *To:* "user@cassandra.apache.org" <user@cassandra.apache.org>
> *Sent:* Friday, June 21, 2013 8:56 PM
> *Subject:* Re: Cassandra driver performance question...
>
>   Thanks Jabbar,
>
> I ran nodetool as suggested and it 0 latency for the row count I have.
>
> I also ran cli list command for the table hit by my JDBC perparedStatement
> and it was slow like 121msecs the first time I ran it and second time I ran
> it it was 40msecs versus jdbc call of 38msecs to start with unless I run it
> twice also and get 1.5-2.5msecs for executeQuery the second time the
> preparedStatement is called.
>
> I ran describe from cli for the table and it said caching is "ALL" which
> is correct.
>
> A real mystery and I need to understand better what is going on.
>
> Regards,
> -Tony
>
>   *From:* Jabbar Azam <ajazam@gmail.com>
> *To:* user@cassandra.apache.org; Tony Anecito <adanecito@yahoo.com>
> *Sent:* Friday, June 21, 2013 3:32 PM
> *Subject:* Re: Cassandra driver performance question...
>
>  Hello Tony,
>
> I would guess that the first queries data  is put into the row cache and
> the filesystem cache. The second query gets the data from the row cache and
> or the filesystem cache so it'll be faster.
>
> If you want to make it consistently faster having a key cache will
> definitely help. The following advice from Aaron Morton will also help
>
> "You can also see what it looks like from the server side.
>
> nodetool proxyhistograms will show you full request latency recorded by the coordinator.
> nodetool cfhistograms will show you the local read latency, this is just the time it
takes
> to read data on a replica and does not include network or wait times.
>
> If the proxyhistograms is showing most requests running faster than your app says it's
your
> app."
>
>
> http://mail-archives.apache.org/mod_mbox/cassandra-user/201301.mbox/%3CE3741956-C47C-4B43-AD99-DAD8AFC3AE7C@thelastpickle.com%3E
>
>
>
>  Thanks
>
> Jabbar Azam
>
>
> On 21 June 2013 21:29, Tony Anecito <adanecito@yahoo.com> wrote:
>
>    Hi All,
> I am using jdbc driver and noticed that if I run the same query twice the
> second time it is much faster.
> I setup the row cache and column family cache and it not seem to make a
> difference.
>
> I am wondering how to setup cassandra such that the first query is always
> as fast as the second one. The second one was 1.8msec and the first 28msec
> for the same exact paremeters. I am using preparestatement.
>
> Thanks!
>
>
>
>
>
>
>
>
>

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