Enabling and disabling the JIT compiler

The Just-In-Time (JIT) compiler dynamically generates machine code for frequently used bytecode sequences in Java™ applications during their execution. The JIT compiler delivers new optimizations as a result of compiler research, improves optimizations implemented in previous versions of the JIT, and provides better hardware exploitation.

The JIT compiles Java bytecode to machine code transparently. You can disable the JIT to help isolate a problem. If a problem occurs when executing a Java application, you can disable the JIT to help isolate the problem. Disabling the JIT is a temporary measure only; the JIT is required to optimize performance.