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Zhihong Ted Yu commented on HBASE-6427: --------------------------------------- Looking at the changes to Compactor.compact(), the new preCompact() takes precedence over existing preCompact() method. This should be documented. My comment above about scanner insertion was not valid. It is not clear why more than one RegionObserver would return InternalScanner from preCompact(). For simplicity, we can break out of the loop in RegionCoprocessorHost.preCompact() when a non-null InternalScanner is returned. This behavior should also be documented. > Pluggable compaction policies via coprocessors > ---------------------------------------------- > > Key: HBASE-6427 > URL: https://issues.apache.org/jira/browse/HBASE-6427 > Project: HBase > Issue Type: New Feature > Reporter: Lars Hofhansl > Assignee: Lars Hofhansl > Priority: Minor > Attachments: 6427-notReady.txt, 6427-v1.txt, 6427-v2.txt, > 6427-v3.txt, 6427-v4.txt, 6427-v5.txt > > > When implementing higher level stores on top of HBase it is necessary to > allow dynamic control over how long KVs must be kept around. > Semi-static config options for ColumnFamilies (# of version or TTL) is not > sufficient. > This can be done with a few additional coprocessor hooks, or by makeing > Store.ScanInfo pluggable. > Was: > The simplest way to achieve this is to have a pluggable class to determine > the smallestReadpoint for Region. That way outside code can control what KVs > to retain. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira