Hi there- In addition to what was said about GC, you might want to double-check this...
http://hbase.apache.org/book.html#performance ... as well as this case-study for performance troubleshooting http://hbase.apache.org/book.html#casestudies.perftroub On 4/24/12 9:58 PM, "Michael Segel" <[email protected]> wrote: >Have you thought about Garbage Collection? > >-Grover > >Sent from my iPhone > >On Apr 24, 2012, at 12:41 PM, "Skchaudhary" <[email protected]> wrote: > >> >> I have a cluster Hbase set-up. In that I have 3 Region Servers. There >>is a >> table which has 27 Regions equally distributed among 3 Region servers--9 >> regions per region server. >> >> Region server 1 has ---region 1-9 Region server 2 has ---region 10-18 >>Region >> server 3 has ---region 19-27 >> >> Now when I start a program which inserts rows in region 1 and region 5 >>(both >> under Region Server-1) alternatively and on continuous basis, I see >>that the >> insert time for each row is not constant or consistent---there is a lot >>of >> variance or say standard deviation of insert time is quite large. Some >>times >> it takes 2 ms to insert a row, sometimes 3 ms,sometimes 1000 ms and >> sometimes even > 3000 ms.Even though data size in rows is equal. >> >> I understand that due to flushing and compaction of Regions the writes >>are >> blocked---but then it should not be blocked for larger span of time and >>the >> blockage time should be consistent for every flush/compaction (minor >> compaction). >> >> All in all every time flush and compaction occurs it should take nearly >>same >> time for each compaction and flush. >> >> For our application we need a consistent quality of service and if not >> perfect atleast we need a well visible boundary lines--like for each row >> insert it will take some 0 to 10 ms and not more than 10 ms(just an >>example) >> that even though minor compaction or flush occurs. >> >> Is there any setting/configuration which I should try? >> >> Any ideas of how to achieve it in Hbase. >> >> Any help would be really appreciated. >> >> Thanks in advance!! >> >> -- >> View this message in context: >>http://old.nabble.com/Hbase-Quality-Of-Service%3A-large-standarad-deviati >>on-in-insert-time-while-inserting-same-type-of-rows-in-Hbase-tp33740438p3 >>3740438.html >> Sent from the HBase User mailing list archive at Nabble.com. >> >
