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From Ted Yu <yuzhih...@gmail.com>
Subject Re: Doubt in Scanner.next()
Date Wed, 11 Jan 2017 18:19:52 GMT
As refguide states, hbase.client.scanner.caching works
with hbase.client.scanner.max.result.size to try and use the network

Make sure the release you use is 1.1.0+ which had important bug fixes
w.r.t. max result size.

On Wed, Jan 11, 2017 at 9:46 AM, Josh Elser <elserj@apache.org> wrote:

> Behind the scenes, the ClientScanner is buffering results from the
> previous RPC. Ignoring multiple RegionServers for now, the caching value
> denotes the number of records that were fetched by the ClientScanner in an
> RPC. When the buffered results are consumed by your client, a new RPC will
> be made to fetch another 100 rows.
> Thus, larger scanner caching values reduces the number of RPCs the
> ClietnScanner object will make; however, it increases the length of the RPC
> itself (as it takes longer to aggregate a larger number of rows to return).
> Rajeshkumar J wrote:
>> I have hbase.client.scanner.caching as 100.  I am scanning a table. For
>> instance say we have 500 rows matching for the current scan. When I give
>> the statement ResultScanner.next() what will happen? whether it will
>> return
>> 100 rows for each next operation or something else
>> Thanks

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