Use C heap when compiling with Just In Time method (JIT compiler) supported by JavaVM. If you execute JIT compiler for methods with large numbers of processing or for large methods, the C heap size allocated for compilation process becomes larger and might result into insufficient C heap. In such cases, problems like forced termination of JavaVM or abnormal end of J2EE server might occur, which might result into complete suspension of the system.

To prevent the occurrence of such problems, you can set an upper limit to the C heap size used in JIT compilation. When the upper limit is exceeded, JIT compiling will be canceled and the subsequent compilation will be executed by interpreter method. Thus, you can prevent the forced termination of JavaVM and stopping of the system.

Specify the upper limit of allocation size of C heap during JIT compilation by using the -XX:HitachiJITCompileMaxMemorySize option. For details on the -XX:HitachiJITCompileMaxMemorySize option, see -XX:HitachiJITCompileMaxMemorySize (option for specifying upper limit of allocated memory during JIT compilation) in the uCosminexus Application Server Definition Reference Guide.