Perl uses reference counting for variables, and hence even reading a variable means increasing the reference count, reading the value, and then decreasing the reference count again. So even a read can cause a memory write in Perl. You don't show much code, so I can't tell whether that's the case with your code, but I think that's a propable explanation.

In reply to Re: WHY copying does happen (fork) by Corion
in thread WHY copying does happen (fork) by Anonymous Monk

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