Hi, I'm having a problem with a large perl program using up even larger amounts of memory. I've been trying to make sense of this by using Devel::Size, Devel::Symdump, but from this I learned that the symbol table contains only a small amount of the total memory the process is using (see Devel::Symdump without Devel::Symdump interference, where I learned that the symbol table doesn't contain lexical scopes (broquaint++)).

Since this post I've been trying to use Padwalker to peek into the lexical scopes I'm in; not very succesfully because this seems to 'hang' when I'm using it in perl-d. The other problem with this is that (as far as I can see) it accesses only the scopes below the point-of-action of Padwalker, not all lexical scopes ('scratchpads') that might have variables or other beasts using up memory.

I've been reading up on the perlguts and related literature, and every variable is stored in a structure (like IV, SV, CV and friends), but I haven't encountered a lot of information on the 'superstructure' that keeps these values organised, and how to get information from this 'superstructure'.

Is there a way of breaking up the total memory-usage of a running perl process (or a core-dump) into variables/other managable units? Perl doesn't return memory that is freed after a variable/object etc. is destroyed. Is it possible to view how much of this 'allocated-unused' memory a running process is keeping occupied? A lot of info can be found on CPU-usage statistics (ie. profiling), any pointers to memory-usage related info appreciated. If my view of how perl memory usage is organised is wrong, I'd like to know as well.

Update: Thanks a lot everybody for your replies, I've learned a lot from it. Thanks gmpassos for pointing out B::TerseSize.

In reply to Memory usage breakup by eXile

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