NonStop Server for Java 5.1 Programmer's Reference

As described earlier, the NonStop Server for Java 5.1 does not support the throughput collector
(specified with the option XX:+UseParallelGC ) or the concurrent low pause collector
(specified with the option XX:+UseConcMarkSweepGC ).
Also, the following options do not apply either for the NonStop Server for Java 5.1 or the
NonStop system:
-XX:+UseBoundThreads  Option to bind user level threads; Solaris specific
-XX:+UseAltSigs  Solaris specific.
-XX:+UseV8InstrsOnly  Only for Sparc (Solaris)
-XX:-AllowUserSignalHandlers  Solaris specific
-XX:AltStackSize=nn  Solaris specific
-XX:+MaxFDLimit  Solaris specific
-XX:-UseBoundThreads  Solaris specific
-XX:-UseLWPSynchronization  Solaris specific
-XX:PreBlockSpin=nn  Only for Linux
-XX:-UseISM  Solaris specific
-XX:-UseMPSS  Solaris specific
-XX:-UseSpinning  Only for Linux
Java GC Profiling
The NonStop Server for Java 5.1 supports an HP proprietary option, -Xverbosegc to capture the GC activity of
the Java application. The output of this tool can be used to view and analyze the detailed statistics in an offline
mode with HPjtune. The -Xverbosegc option prints out detailed information about the spaces within the Java
Heap before and after the garbage collection.
The syntax :
-Xverbosegc[:help]|[0|1][:file=[stdout|stderr|<filename>]]
Fore more infomation on the syntax options of -Xverbosegc, see java in the NonStop Server for Java 5.1
Tools Reference Pages.
JVM Tuning Tools
PrintGCStats is a tool for mining verbose:gc logs that can aid analyzing and tuning garbage collection. You can
download this tool from the following location:
http://java.sun.com/developer/technicalArticles/Programming/turbo/PrintGCStats.zip
For more information on profiling tools, see the Application Profiling section.