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From James Taylor <jamestay...@apache.org>
Subject Re: query client performance
Date Fri, 25 Jul 2014 19:34:27 GMT
Hi Abe,
FWIW, there's an improvement in place
(https://issues.apache.org/jira/browse/PHOENIX-539) for our upcoming
next release that doesn't cause the first rext row call to pull over
everything. Instead, it is done in chunks.

As far as what you can do now, I'd recommend putting a LIMIT clause on
your queries as this will bound the number of rows that get pulled
over. You can also page through the results as described here:
http://phoenix.apache.org/paged.html and elaborated on in this email
thread: http://s.apache.org/588

Thanks,
James

On Fri, Jul 25, 2014 at 10:45 AM, Nicolas Maillard
<nmaillard@hortonworks.com> wrote:
> Hello Abe
>
> You are right currently the pheonix client is the final step hence some
> processing can happen there.
> One way is to actually put the client on the cluster to avoid long anf
> suboptimal networks.
> Maybe a service standing in the cluster for you in front of the client to do
> last stepds and even pagination/compression.
>
>
>
> On Thu, Jul 24, 2014 at 11:24 PM, Abe Weinograd <abe@flonet.com> wrote:
>>
>> Hello,
>>
>> One of our main use cases is to extract a subset of our data in an ETL
>> tool (usually in the 10 million row range) from our tables in Phoenix.  The
>> behavior I am seeing is that all rows are streamed to the machine running
>> the Phoenix Client and then processed before the JDBC driver gets the next
>> row.
>>
>> We have tuned the scanner cache to 1000 rows, however it takes a while.  I
>> can imagine the all rows are being sorted before they are streamed out to
>> the result set.  Is this something we can change?  what other things can I
>> tune for this access pattern?
>>
>> Thanks!
>> Abe
>
>
>
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