Java Virtual Machine data counters

The Java Virtual Machine (JVM) data counters are used to monitor the JVM performance. With an exception to the data counters used for total, used and free heap size, the data counters can be found using the Java Virtual Machine Profiler Interface (JVMPI). To use JVMPI, turn on the monitoring by settting the -XrunpmiJvmpiProfiler command line. See Enabling Java Virtual Machine Profiler Interface data reporting

Data counter definitions

Name	Description	Version	Granularity	Type	Level
Free memory	Free memory in JVM run time	3.5.5 and above	per Java Virtual Machine (JVM)	CountStatistic	Low
Used memory	Used memory in JVM run time	3.5.5 and above	per JVM	CountStatistic	Low
Total memory	Total memory in JVM run time	3.5.5 and above	per JVM	BoundedRangeStatistic. The upperBound and lowerBound are not implemented for the Total memory counter.	High
Up time	The amount of time the JVM is running	5.0	per JVM	CountStatistic	Low
Number garbage collection calls	Number of garbage collection calls. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	CountStatistic	Max
Average time between garbage collection	Average garbage collection in seconds between two garbage collection. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	TimeStatistic	Max
Average garbage collection duration	Average duration of a garbage collection. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	TimeStatistic	Max
num waits for a lock	Number of times that a thread waits for a lock.This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	CountStatistic	Max
avg time waiting for lock	Average time that a thread waits for a lock. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	TimeStatistic	Max
Number of objects allocated	Number of objects allocated in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	CountStatistic	Max
Number of objects found	Number of objects in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	CountStatistic	Max
Number of objects freed	Number of objects freed in heap. This counter is not available unless -XrunpmiJvmpiProfiler is set when starting the JVM.	4.0 and above	per JVM	CountStatistic	Max