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Eshcar Hillel commented on HBASE-19095: --------------------------------------- Basic mode does not use StoreScanner. Basic applies two kinds of steps - a flattening step and a merge step. A merge step creates a MemStoreMergerSegmentsIterator. This iterator manages a KeyValueHeap it uses it to merge the index of several segments, and does not drop any cell. A flattening step simply uses a segment scanner to create a flat index, and does not drop any cell. I would not open these to CP hooks. Other modes (like Eager, and Adaptive which I am about to commit to trunk) may apply a compact step which imitates disk data compaction in-memory. A compact step creates a MemStoreCompactorSegmentsIterator which uses a StoreScanner as described above. Here, I agree there is room to give the user control on the number of versions to keep, TTL etc. > Add CP hooks in RegionObserver for in memory compaction > ------------------------------------------------------- > > Key: HBASE-19095 > URL: https://issues.apache.org/jira/browse/HBASE-19095 > Project: HBase > Issue Type: Sub-task > Components: Coprocessors > Reporter: Duo Zhang > Fix For: 2.0.0-beta-1 > > > This is a hole in our CP hooks. -- This message was sent by Atlassian JIRA (v6.4.14#64029)