The JVM fits into the tree of objects as show in JVM Tree Hierarchy.
The statistics that are available for the Virtual Machine for Java platform (Java Virtual Machine) or JVM machine are shown in the following sections:
Use the following dotted name pattern for JVM class loading system statistics:
server.jvm.class-loading-system.statistic
With Java SE, additional monitoring information can be obtained from the JVM. Set the monitoring level to LOW to enable the display of this additional information. Set the monitoring level to HIGH to also view information pertaining to each live thread in the system. More information about the additional monitoring features for Java SE is available in Monitoring and Management for the Java Platform.
The Java SE monitoring tools are discussed at http://download.oracle.com/docs/cd/E17409_01/javase/6/docs/technotes/tools/.
The statistics that are available for class loading in the JVM for Java SE are shown in the following table.
Table 8–17 JVM Monitoring Statistics for Java SE Class Loading
Statistic |
Data Type |
Description |
---|---|---|
loadedclasscount |
CountStatistic |
Number of classes that are currently loaded in the JVM |
totalloadedclasscount |
CountStatistic |
Total number of classes that have been loaded since the JVM began execution |
unloadedclasscount |
CountStatistic |
Number of classes that have been unloaded from the JVM since the JVM began execution |
The statistics available for threads in the JVM in Java SE are shown in the following table.
Table 8–18 JVM Monitoring Statistics for Java SE - Threads
Statistic |
Data Type |
Description |
---|---|---|
allthreadids |
StringStatistic |
List of all live thread ids. |
currentthreadcputime |
CountStatistic |
CPU time for the current thread (in nanoseconds) if CPU time measurement is enabled. If CPU time measurement is disabled, returns -1. |
daemonthreadcount |
CountStatistic |
Current number of live daemon threads. |
monitordeadlockedthreads |
StringStatistic |
List of thread ids that are monitor deadlocked. |
peakthreadcount |
CountStatistic |
Peak live thread count since the JVM started or the peak was reset. |
threadcount |
CountStatistic |
Current number of live daemon and non-daemon threads. |
totalstartedthreadcount |
CountStatistic |
Total number of threads created and/or started since the JVM started. |
Use the following dotted name pattern for JVM compilation system statistics:
server.jvm.compilation-system.statistic
The statistics that are available for compilation in the JVM for Java SE are shown in the following table.
Table 8–19 JVM Monitoring Statistics for Java SE Compilation
Statistic |
Data Type |
Description |
---|---|---|
name-current |
StringStatistic |
Name of the current compiler |
totalcompilationtime |
CountStatistic |
Accumulated time (in milliseconds) spent in compilation |
Use the following dotted name pattern for JVM garbage collectors statistics:
server.jvm.garbage-collectors.statistic
The statistics that are available for garbage collection in the JVM for Java SE are shown in the following table.
Table 8–20 JVM Monitoring Statistics for Java SE Garbage Collectors
Statistic |
Data Type |
Description |
---|---|---|
collectioncount |
CountStatistic |
Total number of collections that have occurred |
collectiontime |
CountStatistic |
Accumulated time (in milliseconds) spent in collection |
Use the following dotted name pattern for JVM memory statistics:
server.jvm.memory.statistic
The statistics that are available for memory in the JVM for Java SE are shown in the following table.
Table 8–21 JVM Monitoring Statistics for Java SE Memory
Statistic |
Data Type |
Description |
---|---|---|
committedheapsize |
CountStatistic |
Amount of heap memory (in bytes) that is committed for the JVM to use |
committednonheapsize |
CountStatistic |
Amount of non-heap memory (in bytes) that is committed for the JVM to use |
initheapsize |
CountStatistic |
Size of the heap initially requested by the JVM |
initnonheapsize |
CountStatistic |
Size of the non-heap area initially requested by the JVM |
maxheapsize |
CountStatistic |
Maximum amount of heap memory (in bytes) that can be used for memory management |
maxnonheapsize |
CountStatistic |
Maximum amount of non-heap memory (in bytes) that can be used for memory management |
objectpendingfinalizationcount |
CountStatistic |
Approximate number of objects that are pending finalization |
usedheapsize |
CountStatistic |
Size of the heap currently in use |
usednonheapsize |
CountStatistic |
Size of the non-heap area currently in use |
Use the following dotted name pattern for JVM operating system statistics:
server.jvm.operating-system.statistic
The statistics that are available for the operating system for the JVM machine in Java SE are shown in the following table.
Table 8–22 JVM Statistics for the Java SE Operating System
Statistic |
Data Type |
Description |
---|---|---|
arch-current |
StringStatistic |
Operating system architecture |
availableprocessors |
CountStatistic |
Number of processors available to the JVM |
name-current |
StringStatistic |
Operating system name |
version-current |
StringStatistic |
Operating system version |
Use the following dotted name pattern for JVM runtime statistics:
server.jvm.runtime.statistic
The statistics that are available for the runtime in the JVM runtime for Java SE are shown in the following table.
Table 8–23 JVM Monitoring Statistics for Java SE Runtime
Statistic |
Data Type |
Description |
---|---|---|
classpath-current |
StringStatistic |
Classpath that is used by the system class loader to search for class files |
inputarguments-current |
StringStatistic |
Input arguments passed to the JVM; not including arguments to the main method |
managementspecversion-current |
StringStatistic |
Management specification version implemented by the JVM |
name-current |
StringStatistic |
Name representing the running JVM |
specname-current |
StringStatistic |
JVM specification name |
specvendor-current |
StringStatistic |
JVM specification vendor |
specversion-current |
StringStatistic |
JVM specification version |
uptime |
CountStatistic |
Uptime of the JVM (in milliseconds) |
vmname-current |
StringStatistic |
JVM implementation name |
vmvendor-current |
StringStatistic |
JVM implementation vendor |
vmversion-current |
StringStatistic |
JVM implementation version |