See explanation for the following parameter (from hbase refguide) hbase.server.compactchecker.interval.multiplier The number that determines how often we scan to see if compaction is necessary. Normally, compactions are done after some events (such as memstore flush), but if region didn't receive a lot of writes for some time, or due to different compaction policies, it may be necessary to check it periodically. The interval between checks is hbase. server.compactchecker.interval.multiplier multiplied by hbase.server.thread.wakefrequency. Default. 1000 Cheers
On Thu, Aug 21, 2014 at 3:01 AM, chenwenhui <[email protected]> wrote: > From the book named "Hbase: the Definitive Guide", i know that there is a > condition to trigger major compaction, i.e. a thread controlled by > "hbase.server.thread.wakefrequency(10 seconds by default)" and > "hbase.server.thread.wakefrequency.multiplier" checks periodically whether > major compaction. > But i also read that the other conditon, both > "hbase.hregion.majorcompaction(7 days by default)" and > "hbase.hregion.majorcompaction.jitter", can also trigger major compaction. > As my understanding, because of the former, the latter condition will > never execute. > Maybe i mis-undertand the two conditions, anyone can explain the > difference between the two condtions? Thanks!
