OPTIMIZE

Since 2.74 and the port to pcre2, requests JIT compilation, which, if the just-in-time compiler is available, further processes a compiled pattern into machine code that executes much faster.

However, it comes at the cost of extra processing before the match is performed, so it is most beneficial to use this when the same compiled pattern is used for matching many times. Before 2.74 this option used the built-in non-JIT optimizations in pcre1.