http://www.perlmonks.org?node_id=963263

ghosh123 has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monk, I am using Devel::FindRef to find out memory leak in my program. Please explain me the output so that I get a clue where to look into. Suppose I have two module say A.pm and B.pm. I am calling a callback function from A.pm when I Delete a job and the body of the function is defined in B.pm . It is like :

A.pm $menu->add('command' , -label => 'Delete', -command => sub {$self->onMenuDelete(@_)} ); ## Above $self is A B.pm sub B ::onmenuDelete { my B $self = shift; my $temp = $self->{business} ; $self->jobdisplayobj->deleteElements(); print Devel::FindRef::track \$temp; } The output is :REF(0xb20ba50) [refcount 2] is +- referenced by REF(0xbe1398c) [refcount 1], which is | a temporary on the stack. +- the lexical '$temp' in CODE(0xb20b900) [refcount 4], which is +- the global &A::onMenuDelete. +- the global &B::onMenuDelete.

Please explain me the above output. I guess there are 2 references of $temp, one is the stack which is the $temp variable itself. Where is the other hanging?

Replies are listed 'Best First'.
Re: Please explain me this FindRef output
by Khen1950fx (Canon) on Apr 03, 2012 at 19:21 UTC
    The result is a little too mundane. I prefer Devel::Leak. I'd rather see something like this:
    package B; use strict 'refs'; use warnings; use Devel::Leak; my $count = Devel::Leak::NoteSV($handle); my $self = shift @_; my $temp = $$self{'business'}; print "The count is: $count\n"; my $now = Devel::Leak::CheckSV($handle); # more code here print "The count is now: $now\n";
    The output makes more sense to me.
Re: Please explain me this FindRef output
by Anonymous Monk on Apr 03, 2012 at 21:34 UTC