NonStop Server for Java 7.0 Tools Reference Pages

HP Extensions to NonStandard Java Options

-Xabend

Turns on the abend option to abort the process instead of exiting with a non-zero exit code. If the

NonStop Server for Java 7.0 application runs as a Pathway server, you can enable this option to

alert Pathmon to restart the server after NSJ7 application shuts down.

-XX:GuaranteeFreeHeapSizeAfterGC=<number>

Prevents excessive garbage collection (GC) activity in Java applications that have not been tuned

well with respect to GC. If the application uses most of the memory heap and the Java virtual

machine is unable to collect much garbage, excessive GC activity might occur to satisfy the demand

for allocation of new objects. This activity may result in a busy CPU in which the Java application

is executing. To prevent this occurrence, use the

-XX:GuaranteeFreeHeapSizeAfterGC=<number> option, where <number> is specified in

bytes, kilobytes (k), or megabytes (m). After a GC, if the Java virtual machine cannot free the heap

size more than the value specified with the GuaranteeFreeHeapSizeAfterGC option, the Java

virtual machine throws an OutOfMemoryError.

-XX:+ForceStopableMode

Forces the Java process stop mode to 1 (stoppable) when a Java thread transitions to native state.

Under certain rare conditions, the Java Virtual Machine (JVM) can incorrectly be running in

unstoppable mode, which can result in a processor halt if the JVM process hits a trap or exception.

Normally, the process stop mode is set to unstoppable by privileged code when the code is run,

and set back to stoppable mode on exit to the calling routine. While Java itself does not run in

privileged mode when executing Java byte codes, Java application code as well as the JVM can

make calls to native code or system APIs that run privileged code. If any of these privileged routines

do not reset the stop mode on exit, it can result in a processor halt if a trap occurs. Enable this flag

to avoid a processor halt in case the stop mode has been set incorrectly by privileged code. Some

applications may see performance degradation when this flag is enabled.