http://www.perlmonks.org?node_id=1014158


in reply to Re: Timing of garbage collection
in thread Timing of garbage collection

Perl doesn't have "garbage collection" in the sense that it never gives memory back to the OS
Sorry, but that statement is garbage.

First, the statement is wrong, as already demonstrated by BrowserUk. Whether perl releases memory back to the OS or not depends simply on the implementation of malloc/realloc, as described at Re: Not able to release memory (malloc implementation).

Second, whether it returns memory to OS is not related to garbage collection! As already noted by dave_the_m, perl uses a reference-counted garbage collector, so you get "deterministic destructors" for free (i.e. in perl, you are guaranteed that an object is destroyed (and destructor called) immediately its reference count goes to zero). BTW, deterministic destructors are a feature of the C++ RAII idiom yet are problematic when using a mark-and-sweep garbage collector, such as that used by Java, which is why Java has a "finally" clause (see also Dispose pattern).