I am beginning to think that this is a configuration issue on my cluster. Do the following configuration files seem sane ?
hbase-env.sh https://gist.github.com/3345338 hbase-site.xml https://gist.github.com/3345356 Gurjeet On Mon, Aug 13, 2012 at 5:30 PM, lars hofhansl <[email protected]> wrote: > Only 4% in the 12 node cluster case? I'd guess you're using not more cores > then before (i.e. the parallelizing on the client is bad), or you're IO bound > (which is unlikely). > Are all your regionserver busy in terms of CPU? > > > -- Lars > > > > ----- Original Message ----- > From: Gurjeet Singh <[email protected]> > To: [email protected] > Cc: > Sent: Monday, August 13, 2012 3:12 PM > Subject: Re: Slow full-table scans > > Okay, I just ran this experiment. It did speed things up, but only by > 4%. This all still seems awfully slow to me - does someone have > another suggestion ? > > Thanks in advance! > Gurjeet > > On Mon, Aug 13, 2012 at 12:51 AM, Gurjeet Singh <[email protected]> wrote: >> Thanks a lot! >> >> On Mon, Aug 13, 2012 at 12:27 AM, Stack <[email protected]> wrote: >>> On Mon, Aug 13, 2012 at 6:10 AM, Gurjeet Singh <[email protected]> wrote: >>>> Thanks Lars! >>>> >>>> One final question : is it advisable to issue multiple threads >>>> against a single HTable instance, like so: >>>> >>>> HTable table = ... >>>> for (i = 0; i < 10; i++) { >>>> new ScanThread(table, startRow, endRow, rowProcessor).start(); >>>> } >>>> >>> >>> Make an HTable per thread. See the class comment: >>> http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/HTable.html >>> >>> St.Ack >
