Just in Time Compilation Storing vs Doing always
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I undertsand that JIT compilation is compilation to native code using hotspot mechanisms, which can be very very fast as it is optimization to the OS, Hardwards, etc.

My question is, why Java not stores that JIT complied code somewhere in file and use the same for future purposes? This can reduce the 'initial warm-up' time as well. 

Please let me know what I am missing here.