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This option enables or disables the storage of VM classes created through Unsafe.defineClass in the shared classes cache.

The option is enabled by default, which means that unsafe classes are stored in the shared classes cache and are therefore available for ahead-of-time (AOT) compilation, potentially improving startup performance.


Setting Effect Default
-XX:+ShareUnsafeClasses Enable yes
-XX:-ShareUnsafeClasses Disable

See also