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-XX:[+|-]PerfTool

This option enables or disables JIT support for the perf tool without affecting the existing Xjit options.

Restriction: Since this option creates a file that is used by the Linux® system profiler, perf, it applies only to Linux.

Syntax

    -XX:[+|-]PerfTool
Setting Effect Default
-XX:+PerfTool Enable
-XX:-PerfTool Disable yes

Explanation

The -XX:+PerfTool option is a stand-alone alternative for the existing -Xjit:perfTool option. If multiple -Xjit options exist, only the last option takes effect. Therefore, if the -Xjit:perfTool option is added later, it overrides the existing -Xjit options. To overcome this issue, the XX:+PerfTool option enables JIT support for the perf tool without having any impact on the existing Xjit options. This enabling option creates a /tmp/perf-<pid>.map file that is used by the perf tool to map the samples in the JIT-compiled code to the corresponding Java method names.

To disable the JIT support for the perf tool, set the -XX:-PerfTool option on the command line.

See also