JVM Monitoring

This section describes the types, names, and meanings of JVM metrics collected by APM.

**Table 1** Collection parameters for JVM monitoring
Parameter	Data Type	Application Type	Default	Supported Start Agent Version	Supported End Agent Version	Description
Trace Stack Collection Threshold	integer	JAVA	0	2.0.4	-	Stacks will be automatically printed when the request latency exceeds the threshold.

**Table 2** JVM monitoring metrics
Category	Metric	Name	Description	Unit	Data Type	Default Aggregation Mode
Class loading (classLoading: JVM class loading statistics)	loadedClassCount	Loaded Classes	Number of loaded classes	-	INT	SUM
	totalLoadedClassCount	Total Loaded Classes	Total number of loaded classes	-	INT	SUM
	unloadedClassCount	Unloaded Classes	Number of unloaded classes	-	INT	SUM
Compilation (compile: JVM class compilation time statistics)	compilationTime	Compilation Time	Compilation time in a collection period	ms	INT	SUM
	totalCompilationTime	Total Compilation Time	Total compilation time	ms	INT	SUM
CPU (CPU: CPU usage statistics of JVM processes)	cpuRatio	CPU Usage	CPU usage of the Java process	%	DOUBLE	AVG
	cpuRatioMax	Max. CPU Usage	Maximum CPU usage of the Java process	%	DOUBLE	MAX
	cpuTimeInterval	CPU Time	CPU time of the Java process in the collection interval	ns	INT	SUM
	processorCount	Processors	Number of processors	-	INT	SUM
	systemTimeInterval	Collection Interval	Collection interval	ns	INT	SUM
	totalCpuTime	Total CPU Time	Total CPU time	ns	INT	SUM
Memory (memory: JVM memory statistics)	directMemoryUsage	Direct Memory	Used direct memory	M	INT	AVG
	directMemoryCapacity	Direct Memory Capacity	Total direct memory capacity	M	INT	AVG
	heapMemoryUsage	Heap Memory	Used heap memory	M	INT	AVG
	nonHeapMemoryUsage	Non-Heap Memory	Used non-heap memory	M	INT	AVG
	objectPendingFinalizationCount	Objects Being Recycled	Number of objects that are being recycled at the time of collection	-	INT	SUM
Memory pool (memoryPool: statistics collected by JVM memory pool)	committed	Available Memory	Available memory	M	INT	SUM
	init	Initialized Memory	Initialized memory	M	INT	SUM
	max	Max. Memory	Maximum memory	M	INT	SUM
	name	Memory Pool Name	Memory pool name	-	ENUM	LAST
	used	Used Memory	Used memory	M	INT	SUM
Thread (thread: JVM thread statistics)	currentThreadCpuTime	Thread CPU Time	CPU time of the current thread	-	INT	SUM
	currentThreadUserTime	Thread User Time	User time of the current thread	-	INT	SUM
	daemonThreadCount	Daemon Threads	Number of daemon threads	-	INT	SUM
	deadlockedThreadsCount	Deadlock Threads	Number of deadlock threads	-	INT	SUM
	monitorDeadlockedThreads	Current Deadlock Threads	ID list of current deadlock threads	-	INT	SUM
	peakThreadCount	Max. Threads Executed	Maximum number of threads executed	-	INT	SUM
	threadCount	Current Threads	Number of current threads	-	INT	SUM
	totalStartedThreadCount	Total Threads	Total number of threads that are started since the Java process is started	-	INT	SUM
	newThreadCount	Initial Threads	Number of threads in the initial state	-	INT	SUM
	runnableThreadCount	Running Threads	Number of running threads	-	INT	SUM
	blockedThreadCount	Blocked Threads	Number of blocked threads	-	INT	SUM
	waitingThreadCount	Pending Threads	Number of pending threads	-	INT	SUM
	timedWaitingThreadCount	Timed-out Threads	Number of threads that timed out	-	INT	SUM
	terminatedThreadCount	Terminated Threads	Number of terminated threads	-	INT	SUM