Thanks for your reply. Please see my comment inline. Thanks & Best regards LiuJinglong
2010/9/26 Stack <[email protected]> > On Sat, Sep 25, 2010 at 9:32 PM, baggio liu <[email protected]> wrote: > > Hi HBaser, > > we meet a problem when a meta region down then another region server > load > > region. a region server core. > > It core dumps? > > Yes, it's core dump > > > out machine enviroment: > > 8 cores CPU, 48G memory, 12 1T disks > > our region server heap size : 36000 > > jdk > > java version "1.6.0_07" > > This is an old JVM. A lot of bugs have been fixed since this version > was released. Can you update? Especially given you have so many > cores and a bunch of RAM. > > > Sure, our HBase cluster has not released, we'll try to use another version jvm. (u14) > > > > Java(TM) SE Runtime Environment (build 1.6.0_07-b06) > > Java HotSpot(TM) 64-Bit Server VM (build 10.0-b23, mixed mode) > > our jvm parameter like below: > > -XX:+UseConcMarkSweepGC -XX:+UseParNewGC > -XX:+UseCMSCompactAtFullCollection > > -XX:CMSFullGCsBeforeCompaction=0 -XX:+CMSClassUnloadingEnabled > > -XX:-CMSParallelRemarkEnabled -XX:CMSInitiatingOccupancyFraction=70 > > -XX:SoftRefLRUPolicyMSPerMB=0 -XX:MaxTenuringThreshold=7 > > > > This looks like an interesting configuration. How did you arrive at > it (especially max tenuring threshold = 7 and > cmsfulgcsbeforecompaction). > > In fact, we are not very clear effect of these configurations in performance . These config are tuning in our Hadoop cluster(namenode) according to experience. > > And I attach hs_err.log > > Has anyone met this issue ?? > > or If I can get your jdk version and cluster environment is more > > pleasure. > > > > At SU we run u14. u18 is generally regarded as bad. u20 may have > issues. u21, the latest, purportedly has some improved heuristics to > help w/ heap fragmentation. > > Try updating the jvm first. > Our production cluster (hadoop) use u7, and it seems stable. How do you choose u14, because some issues in jdk before ?? What about u16 ?? I just see jdk community recommend this version. > > St.Ack > > > > Thanks & Best regards > > LiuJinglong > > > > > > > > > > >
