NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator's Guide

Configuring NSJSP
NonStop Servlets for JavaServer Pages (NSJSP) 6.1 System Administrator’s Guide—596210-006
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The Installation-Specific servlet.config File
Xms
Specifies the initial memory allocation pool (also called the heap) size that is
allocated when NSJSP starts up. This value is set to the same value as Xmx.
Xss
Specifies the stack size. The default value is 128k.This value should be sufficient
for most applications hosted on NSJSP. If you experience stack overflow
exceptions in your application, consider increasing this value.
Xnoclassgc
Disables the class garbage collection. This argument is specified by NSJ.
When you specify -XnoClassGC in the Arglist of servlet.config file in
<NSJSP_HOME>/conf directory, the class objects in the web applications are left
as it is during garbage collection, and are always considered to be active. Turning
off the garbage collection class eliminates the overhead of loading and unloading
the same class multiple times. If we want to periodically check and reduce the
consumption of the heap memory, -XnoClassGC can be removed from the
Arglists of servlet.config file. However, this creates a small overhead of
running the garbage collection mechanism to free the heap space occupied.
Example 3-24 shows the default Xmx, Xms, Xss, and Xnoclassgc variables.
java.compiler
The java.compiler argument is not set in NSJSP 6.1 for the following reason:
In releases prior to NSJ 4.2 where the Just In Time (JIT) compiler was used, the
java.compiler argument was used to disable JIT compilation. Starting with the
NSJ 4.2 release, the JIT compiler is replaced with the HotSpot compiler. However,
for backward compatibility, the java.compiler argument is still supported. If you
set the value to none, the HotSpot compiler is disabled, which is the equivalent of
setting the -Xint argument. HP recommends that you must not use the
java.compiler argument in order to allow the JVM to use the default value for
the HotSpot compiler.
java.util.logging.manager
Specifies the LogManager that must be used for all logging purposes. Do not
modify this value unless you want to implement a new logging infrastructure. For
more information about logging, see Chapter 5, Logging in NSJSP
. For more
information about the Java logging infrastructure, see
http://java.sun.com/javase/6/docs/technotes/guides/logging/index.html
Example 3-24. The Default Xmx, Xms, Xss, and Xnoclassgc Variables
Arglist -Xmx64m -Xms64m -Xss128k -Xnoclassgc