[HBASE-6602] Region Server Dynamic Metrics can cause high cpu usage.

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Fix Version/s: 0.94.2
• Hadoop Flags: Reviewed
• Assignee: Elliott Neil Clark
• Reporter: Elliott Neil Clark
• Created: 16/Aug/12 23:16
• Updated: 24/Oct/12 05:40
• Resolved: 17/Aug/12 19:03

Description

When regions are getting added and removed lots of cpu time can be used by jmx. This is caused by sending jmx messages for every new metric that is added or removed.

Seeing jstacks like this:

"RMI TCP Connection(3)-10.4.19.33" daemon prio=10 tid=0x00007f9d64b1d000 nid=0x353 runnable [0x00007f9d598d6000]
java.lang.Thread.State: RUNNABLE
at java.util.HashMap.put(HashMap.java:374)
at org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase.createMBeanInfo(MetricsDynamicMBeanBase.java:103)
at org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase.updateMbeanInfoIfMetricsListChanged(MetricsDynamicMBeanBase.java:75)
at org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase.getAttribute(MetricsDynamicMBeanBase.java:133)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:666)
at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:638)
at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1404)
–
at java.util.TimerThread.run(Timer.java:462)

"Timer thread for monitoring hbase" daemon prio=10 tid=0x00007f9d648fe000 nid=0x2b5 runnable [0x00007f9d624c7000]
java.lang.Thread.State: RUNNABLE
at java.util.HashMap.put(HashMap.java:374)
at org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase.createMBeanInfo(MetricsDynamicMBeanBase.java:103)
at org.apache.hadoop.metrics.util.MetricsDynamicMBeanBase.updateMbeanInfoIfMetricsListChanged(MetricsDynamicMBeanBase.java:75)
at sun.reflect.GeneratedMethodAccessor29.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.hadoop.hbase.regionserver.metrics.RegionServerDynamicMetrics.setNumericMetric(RegionServerDynamicMetrics.java:105)