That is pretty much how it works. Perl will save the old memory for reuse, and the new hash will use that left over memory. If you make the hash a global, and "clean it out", it will reuse the same mem over and over, and memory usage will rise to the "peak" level of the biggest hash. Perl (and almost any other program) will not release memory back to the OS.... it figures if you used it once, you may need it again, so it holds on to it. If you want to release the mem back to the OS, use C (which will allow you to deallocate the mem), or "fork and exec" the subroutine, and mem will be truly released at the end of the exec.
I'm not really a human, but I play one on earth. Cogito ergo sum a bum

In reply to Re^3: How to destroy variables and hash? by zentara
in thread How to destroy variables and hash? by PerlPhi

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