What happens to memory after is has been removed from perl (shift/undef/delete etc)?
It is 'put back' into the memory pool perl uses when allocating memory. So when you undef something, the memory that it used becomes available again to be re-allocated.
Can it be reused by other apps?
No, only once the process has exitted will the memory be available to to other apps. This is an OS issue, not a perl issue. See. the recent Memory leak when using hash 'references' for more info on the topic.
HTH

_________
broquaint

In reply to Re: Memory usage and perl by broquaint
in thread Memory usage and perl by Anonymous Monk

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