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From Rajeshkumar J <rajeshkumarit8...@gmail.com>
Subject hbase.client.scanner.caching
Date Tue, 24 Jan 2017 11:25:35 GMT



Number of rows that we try to fetch when calling next on a scanner if it is
not served from (local, client) memory. This configuration works together
with hbase.client.scanner.max.result.size to try and use the network
efficiently. The default value is Integer.MAX_VALUE by default so that the
network will fill the chunk size defined by
rather than be limited by a particular number of rows since the size of
rows varies table to table. If you know ahead of time that you will not
require more than a certain number of rows from a scan, this configuration
should be set to that row limit via Scan#setCaching. Higher caching values
will enable faster scanners but will eat up more memory and *some calls of
next may take longer and longer times when the cache is empty*. Do not set
this value such that the time between invocations is greater than the
scanner timeout; i.e. hbase.client.scanner.timeout.period



Can any one explain the lines which are in bold.


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