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-XcompilationThreads

Use this option to specify the number of compilation threads that are used by the JIT compiler.

Syntax

    -XcompilationThreads<n>
Where <n> is the number of threads. The minimum value is 1. The default and maximum values depend on whether the VM is running with the JITServer feature enabled and if so, whether the VM is running as a JITServer server, as shown in the following table:
JIT compiler scenario Default value Maximum value
JIT and JITServer client Determined by internal JIT heuristics that consider the number of CPUs that the VM is allowed to use 15
JITServer server 63 999
Any number outside this range is ignored. Setting the compilation threads to zero does not disable the JIT compiler. If you want to disable the JIT, use the -Xint option.

Explanation

When multiple compilation threads are used, the JIT might generate several diagnostic log files. A log file is generated for each compilation thread. The naming convention for the log file generated by the first compilation thread uses the following pattern:

<specified_filename>.<date>.<time>.<pid>

The first compilation thread has ID 0. Log files generated by the second and subsequent compilation threads append the ID of the corresponding compilation thread as a suffix to the log file name. The pattern for these log file names is as follows:

<specified_filename>.<date>.<time>.<pid>.<compilation_thread_ID>

For example, the second compilation thread has ID 1. The result is that the corresponding log file name has the form:

<specified_filename>.<date>.<time>.<pid>.1

See also