Performance Management Guide

Monitoring Java

There are several tools to monitor and identify performance inhibitors in your Java application.

vmstat

This command provides information about various system resources. It reports statistics on kernel threads in the run queue as well as in the wait queue, memory usage, paging space, disk I/O, interrupts, system calls, context switches, and CPU activity.

iostat

This command reports detailed disk I/O information.

topas

This command reports CPU, network, disk I/O, Workload Manager and process activity.

tprof

This command can be used to profile the application to pinpoint any hot routines/methods which often can be considered performance problems.

ps -mo THREAD

This command shows to which CPU a process or thread is bound.

Java profilers [-Xrunhprof, Xrunjpa64 (64-bit kernel), -Xrunjpa 32-bit kernel)]

Used to determine which routines or methods are the most heavily used.

java -verbose:gc

This option can be used to check the impact of garbage collection on your application. It reports total time spent doing garbage collection, average time per garbage collection, average memory collected per garbage collection, and average objects collected per garbage collection.