Can I reproduce some of the optimizations made by the JVM manually?

Question

I am working on a Sudoku solver in school, and we have a little competition. Now my algorithm is pretty fast in the first run (about 2.5 ms), but even faster when I solve the same puzzle 10,000 times (about 0.5 ms for each run). Of course, this time depends on the puzzle being solved. I know that the JVM does some optimization when the method is called several times, and this is what I suspect is happening.

I don’t think that I can further optimize the algorithm itself (although I will continue to search), so I was wondering if I could reproduce some of the optimizations performed by the JVM.

Note: compiling to native code is not an option.

Thank!

Edit: All these parameters of the virtual machine are good, but are not really “legal” in the competition of algorithms, since everyone can use these parameters and increase productivity. I am looking for code optimization.

Answer 1

tl; dr : no, most optimizations performed by the JVM cannot be expressed in Java bytecode.

At its core, Java byte code defines your code at a very high level.

This is by design and is one of the reasons why the JVM can perform all these optimizations: the byte code describes the operations at a relatively high level and leaves the actual data on the JVM's execution.

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