Thanks Andrew. Does the stateless scan supports filter? I read the doc you 
referenced, but seems that only the follow parameters are supported, filter is 
not part of the list. 


startrow - The start row for the scan.
endrow - The end row for the scan.
columns - The columns to scan.
starttime, endtime - To only retrieve columns within a specific range of 
version timestamps, both start and end time must be specified.
maxversions - To limit the number of versions of each column to be returned.
batchsize - To limit the maximum number of values returned for each call to 
next().
limit - The number of rows to return in the scan operation.






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发件人: Andrew Purtell
发送时间: ‎2014‎年‎8‎月‎8‎日, ‎星期五 ‎4‎:‎46
收件人: user@hbase.apache.org





On Wed, Aug 6, 2014 at 11:20 PM, SiMaYunRui <myl...@hotmail.com> wrote:

> Further investigation showsthat if I repeatedly fetch data very quick, the
> latter scanner creations are very fast (< 100ms), but if there is >1minute
> interval between two data fetching, the latter is slow.
> ​
> I am certain that it’s not caused by TCP/SSL handshake (fiddler proves
> that). So I believe there must be a resource reuse somewhere no matter in
> Rest service code or hbase server code.​


​Stargate functions as a client to the HBase cluster. Both the RPC client -
here, Stargate - and the RPC server - here, the RegionServer(s) - have
configurable intervals for keeping idle connections around. Either the
client or server will eventually drop the connection. Who does it depends
on the configured timeouts. You can increase the defaults but it would be
better not to hold scanner resources open.

If you are using version 0.98, we have a new stateless scanning option that
avoids the setup costs of old style scanners. See
https://hbase.apache.org/apidocs/org/apache/hadoop/hbase/rest/package-summary.html#operation_stateless_scanner



-- 
Best regards,

   - Andy

Problems worthy of attack prove their worth by hitting back. - Piet Hein
(via Tom White)

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