On Mon, May 16, 2016 at 4:55 PM, Shushant Arora <shushantarora09@gmail.com>
wrote:
> Hi
>
> Hbase uses MVCC for achieving consistent result for Get operations .
> To achieve MVCC it has to maintain multiple versions of same row/cells .
> How many max version of a row/cell does Hbase keeps at any time to support
> MVCC.
>
> Since say multiple gets started one after the other and has not completed
> yet and multiple puts are also occuring in between . Thus it maintains all
> versions whose read point is still in use ?
>
>
Yes.
All ongoing Gets/Scans are registered on startup with their current
readpoint (see HRegion; see constructor for HRegionScannerImpl). Any Put
that falls inside the readpoint of currently ongoing Gets/Scans will be
preserved while the Get/Scan is ongoing.
St.Ack
> Thanks!
>
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