Sun Microsystems 820433510 Java Virtual Machine JVM Statistics, Transaction Service Statistics

About Monitoring

TABLE 18–15Transaction Service Statistics		(Continued)
Statistic	Data Type	Description
committedcount	CountStatistic	Number of transactions that have been
		committed.
rolledbackcount	CountStatistic	Number of transactions that have been
		rolled back.
state	StringStatistic	Indicates whether or not the transaction
		has been frozen.

Java Virtual Machine (JVM) Statistics

The JVM has monitorable attributes that are always enabled. The statistics available for the JVM are shown in the following table.

TABLE 18–16	JVM Statistics
Statistic		Data Type	Description
heapsize		BoundedRangeStatistic	The resident memory footprint with the
			higher and lower bounds of the JVM’s
			memory heap size.
uptime		CountStatistic	The amount of time the JVM has been
			running.

JVM Statistics in Java SE

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 on the additional monitoring features for Java SE is available in a document titled Monitoring and Management for the Java Platform, which is available from http://java.sun.com/javase/6/docs/technotes/guides/management/.

The Java SE monitoring tools are discussed at

http://java.sun.com/javase/6/docs/technotes/tools/#manage.

The statistics available for class loading in the JVM in Java SE are shown in the following table.

TABLE 18–17JVM Statistics for Java SE- Class Loading

Statistic	Data Type	Description
loadedclasscount	CountStatistic	Number of classes that are currently
		loaded in the JVM.

Chapter 18 • Monitoring Components and Services 187