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ryan rawson commented on HBASE-2265: ------------------------------------ done On Tue, Jul 13, 2010 at 3:06 PM, Pranav Khaitan > HFile and Memstore should maintain minimum and maximum timestamps > ----------------------------------------------------------------- > > Key: HBASE-2265 > URL: https://issues.apache.org/jira/browse/HBASE-2265 > Project: HBase > Issue Type: Improvement > Components: regionserver > Reporter: Todd Lipcon > Assignee: Pranav Khaitan > Fix For: 0.90.0 > > Attachments: TimestampOptimizationV6.patch > > > In order to fix HBASE-1485 and HBASE-29, it would be very helpful to have > HFile and Memstore track their maximum and minimum timestamps. This has the > following nice properties: > - for a straight Get, if an entry has been already been found with timestamp > X, and X >= HFile.maxTimestamp, the HFile doesn't need to be checked. Thus, > the current fast behavior of get can be maintained for those who use strictly > increasing timestamps, but "correct" behavior for those who sometimes write > out-of-order. > - for a scan, the "latest timestamp" of the storage can be used to decide > which cell wins, even if the timestamp of the cells is equal. In essence, > rather than comparing timestamps, instead you are able to compare tuples of > (row timestamp, storage.max_timestamp) > - in general, min_timestamp(storage A) >= max_timestamp(storage B) if storage > A was flushed after storage B. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.