Recently I identified one memory leak on my webservice daemon (pure perl), and find resources to do it...
Check modules Find::Globals, Devel::Size. These modules work on solaris box, but on linux other modules area available with some libraries dependencies (Devel::Leak, Devel::LeakTrace), but I don't used it.

My compare with Devel::FindGlobals are text based:

use Devel::FindGlobals;
  open(D, "> $0." . time() );
  print D "Globals: ", print_globals_sizes(), "\n";
  close(D);
__END__
Globals:
Name of SCALAR variable                     Size       Total Size
=================================================================
$AutoLoader::AUTOLOAD                         48               48
$AutoLoader::VERSION                          29               29
$Benchmark::VERSION                           20               20
$Benchmark::cache                             16               16
... cut ...
$Carp::Verbose                                16               16
$Class::ReturnValue::()                       28               28
$Class::ReturnValue::VERSION                  29               29
$Click21::Dist::VERSION                       20               20
$Click21::Dominio                             16             1625
$Click21::Dominio::VERSION                    20               20
... cut ...
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After make two logs on pré-defined points, make a diff to identify size changes. .............