In HBase 0.90.0 there is a new "retain assignment" configuration parameter that makes it so your cluster keeps the same region assignment between full cluster restarts. It is ON by default.
JG > -----Original Message----- > From: Tao Xie [mailto:[email protected]] > Sent: Thursday, January 20, 2011 6:37 PM > To: [email protected] > Subject: performance regression after hbase restart > > hi, I know regions will be reassigned when hbase cluster restarts. My > regionserver and my datanode sit on same physical node. So in my tests after > I restart hbase cluster, performance number drops, I guess this is due to data > locality problem. But in a further experiment, I increase the replication > factor > to cluster size ( I have 8 nodes). After restart and major compaction, the > performance still cannot catch up with the best scenario. I checked datanode > log, most hdfs read has same src and dest node. > > Anyone give me some hints on this? I wonder if anything happens during > region reassignment. > > Thanks. > > Tao
