Liang, Thanks. I wasn’t really aware that the direct memory could get that large. (Full disclosure, we did switch from jdk1.6.0_25 to jdk1.6.0_31 the last time we restarted HBase.)
I've only seen explicit setting of -XX:MaxDirectMemorySize for regionservers associated with the experimental off-heap cache. Is anyone else running their region servers with -XX:MaxDirectMemorySize (not using the off-heap cache)? Ron -----Original Message----- From: 谢良 [mailto:[email protected]] Sent: Tuesday, January 22, 2013 9:20 PM To: [email protected] Subject: 答复: Region server Memory Use is double the -Xmx setting Please set "-XX:MaxDirectMemorySize" explicitly, else the default is taking the value like -Xmx in currenty JDK6, at least for jdk1.6.30+ Best Regards, Liang ________________________________________ 发件人: Buckley,Ron [[email protected]] 发送时间: 2013年1月23日 5:17 收件人: [email protected] 主题: Region server Memory Use is double the -Xmx setting We have a 50 node cluster replicating to a 6 node cluster. Both clusters are running CDH4.1.2 and HBase 0.94.2. Today we noticed that the region servers at our replica site are using 10GB more memory than the '-Xmx12288m' we have defined in hbase-env.sh These region servers have been up since January 9, 2013. Does anyone have suggestions about tracking down this additional memory use? I'm not necessarily expecting the Region Server to stay right at the 12GB that we allocated, but having it running at 24GB is starting to cause the servers to swap. PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 28544 prodcon 18 0 24.1g 23g 18m S 20.0 74.0 9071:34 java 28544: /usr/java/jdk1.6.0_31/bin/java -XX:OnOutOfMemoryError=kill -9 %p -Xmx12288m -Dcom.sun.management.jmxr emote.ssl=false -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.port=9021 -ea -server -XX:+HeapDumpOnOutOfMemoryError -Xmn256m -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOc cupancyFraction=70 -verbose:gc -XX:+PrintGCDetails -XX:+PrintGCDateStamps -Xloggc:/drive1/hadoop/2.0/isoft/../ hbase/logs/gc-hbase.log -ea -server -XX:+HeapDumpOnOutOfMemoryError -Xmn256m -XX ---------------------------------------------------------------------- Ron Buckley x6365 http://intranet-wiki.oclc.org/wiki/XWC/XServe/SRU http://intranet-wiki.oclc.org/wiki/FIND http://intranet-wiki.oclc.org/wiki/Higgins http://intranet-wiki.oclc.org/wiki/Firefly
