Java Virtual Machine counters

 

The JVM counters are used to monitor the JVM performance. With an exception to the counters used for total, used and free heap size, you can find the counters by using the Java Virtual Machine Profiler Interface (JVMPI).

Turn on monitoring with the -XrunpmiJvmpiProfiler command line option.

Name	Key	Description	Granularity	Type	Level
Free memory (KB)	jvmRuntimeModule.freeMemory	Free memory in JVM run time	Per JVM	CountStatistic	Low
Used memory (KB)	jvmRuntimeModule.usedMemory	Used memory in JVM run time	Per JVM	CountStatistic	Low
Total memory (KB)	jvmRuntimeModule.totalMemory	Total memory in JVM run time	Per JVM	BoundedRangeStatistic. The upperBound and lowerBound are not implemented for the Total memory counter.	High
JVM up time (seconds)	jvmRuntimeModule.upTime	The amount of time the JVM is running	Per JVM	CountStatistic	Low
Num GC calls	jvmRuntimeModule.numGcCalls	Number of garbage collection calls. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Avg time between GC calls (ms)	jvmRuntimeModule.avgTimeBetweenGcCalls	Average garbage collection in seconds between two garbage collection. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	TimeStatistic	Max
Avg GC duration (ms)	jvmRuntimeModule.avgGcDuration	Average duration of a garbage collection. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	TimeStatistic	Max
Num waits for lock	jvmRuntimeModule.numWaitsForLock	Number of times that a thread waits for a lock. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Avg time wait for lock	jvmRuntimeModule.avgTimeWaitForLock	Average time that a thread waits for a lock. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	TimeStatistic	Max
Num objects allocated	jvmRuntimeModule.numObjectsAllocated	Number of objects allocated in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Num objects moved	jvmRuntimeModule.numObjectsMoved	Number of objects in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Num objects freed	jvmRuntimeModule.numObjectsFreed	Number of objects freed in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Num started threads	jvmRuntimeModule.numThreadsStarted	Number of threads started. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max
Num dead threads	jvmRuntimeModule.numThreadsDead	Number of threads dies. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	Per JVM	CountStatistic	Max

 

See Also

Enabling Java Virtual Machine Profiler Interface data reporting
Performance data organization

 

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