HP-UX Programmer's Guide for Java 2

or file systems from that disk to a lesser used disk or to a new disk. See “Use
HPjmeter to detect bottlenecks” (page 36).
4. If %idle is frequently equal to zero, or if runq-sz (runqueue size) is frequently
high (eight or more), the system is CPU bound. If system throughput is less than
desired, upgrade to a faster processor or reduce computational load on the system.
5. Check the capacity of the system tables for processes, inode cache, and file
descriptors. These are labeled proc-sz, inod-sz, and file-sz. If the current
utilization is too close to the maximum available, increase the corresponding
HP-UX kernel parameter (nproc, ninode, or nfile). When increasing nfile,
increase nflocks proportionally.
Additional suggestions
• Increasing the size of the buffer cache takes memory away from the pool of free
memory, so be sure that you do not force the system to start swapping or paging.
Thus, increasing the size of the buffer cache may require installing more memory
on the system.
• You can reduce computational load on the system by changing some operational
procedures (such as doing backups at night) or tuning the application to make it
more efficient. Profile the application software using -eprof to look for
performance bottlenecks, then use the HPjmeter performance analysis tool.
Use HPjconfig to tune system parameters
HPjconfig is a Java™ configuration tool for tuning your HP-UX 11.0 or 11i PA-RISC or
Itanium system kernel parameters to match the characteristics of your application.
HPjconfig recommends kernel parameters tailored to your Java™ enterprise services
(web server, application server, etc.) and HP-UX hardware platform. HPjconfig is a
pure Java™ Application that runs on the HP-UX SDK or JRE for the Java™ 2 Platform
version 1.2.2 or later (for which HP-UX 11.00 or later is required).
Download the latest free version of HPjconfig
Use HPjmeter to detect bottlenecks
HPjmeter is a Java™ specific profiler, a platform-independent performance analysis
tool. It helps detect performance bottlenecks by graphically displaying profiling data.
HPjmeter uses a profiling data file from your application, which you obtain by using
the -eprof, -Xeprof, or -Xrunhprof option, depending on your Java™ version. If
you are using SDK 1.3.1 or later, you can also use HPjmeter's lock contention metric to
analyze lock contention between threads.
• Download the latest free version of HPjmeter
Use the -Xverbosegc option to profile garbage collection
-Xverbosegc option is garbage collection profiling, developed specifically for Java™
running on HP-UX. For more information, see Chapter 2 (page 8). See also "Java™
36 Measuring System Performance