Devel::SizeMe - Perl extension for finding the memory usage of Perl variables

SYNOPSIS

use Devel::SizeMe qw(size total_size);

my $size = size("A string");
my @foo = (1, 2, 3, 4, 5);
my $other_size = size(\@foo);
my $total_size = total_size( $ref_to_data );

DESCRIPTION

Acts like Devel::Size 0.77 is the PERL_DMEM env var is not set.

Except that it also provides perl_size() and heap_size() functions.

If PERL_DMEM env var is set to an empty string then all the *_size functions dump a textual representation of the memory data to stderr.

If PERL_DMEM env var is set to a string that starts with "|" then the remainder of the string is taken to be a command name and popen() is used to start the command and the raw memory data is piped to it.

If PERL_DMEM env var is set to anything else it is treated as the name of a file the raw memory data should be written to.

The dmemtree.pl script can be used to process the raw memory data. Typically run via the PERL_DMEM env var. For example:

export PERL_DMEM='|./dmemtree.pl --text'
export PERL_DMEM='|./dmemtree.pl --dot=dmemtree.dot'
export PERL_DMEM='|./dmemtree.pl --db=dmemtree.db'

The --text output is similar to the textual representation output by the module when the PERL_DMEM env var is set to an empty string.

The --dot output is suitable for feeding to Graphviz.

The --db output is a SQLite database. (Very subject to change.)

Example usage:

PERL_DMEM='|./dmemtree.pl --db=dmemtree.db' perl -MDevel::Size=:all -e 'total_size(sub { })'

The dmemview.pl script is a Mojolicious::Lite application that serves data to an interactive treemap visualization of the memory use. It can be run as:

dmemview.pl daemon

and then open http://127.0.0.1:3000

Build and Install

To build and install this module, you need:

Perl
a working C or C++ compiler
a make (or namke on Windows) utility

Follow these steps:

On Linux, Cygwin, or Unix:

perl Makefile.PL
make
make test
sudo make install

On Windows:

perl Makefile.PL
nmake
nmake test
nmake install

BUGREPORTS

Please report bugs to:

http://rt.cpan.org/NoAuth/Bugs.html?Dist=Devel-SizeMe

COPYRIGHT

Copyright (C) 2005 Dan Sugalski, Copyright (C) 2007-2008 Tels, Copyright (C) 2008 BrowserUK, Copyright (C) 2011-2012 Nicholas Clark, Copyright (C) 2012 Tim Bunce.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl v5.8.8.

TODO

Random notes...

Refactoring:

Devel::SizeMe::Core - loads XS and sets options
Devel::SizeMe - loads Devel::SizeMe::Core
    -d:SizeMe=opts?
Devel::SizeMe::Stream - parse raw stream
Devel::SizeMe::Store - db write
Devel::SizeMe::Data - db read / orlite?
Devel::SizeMe::Graph - data reading/processing for sizeme_graph
sizeme_store - script wrapper for Devel::SizeMe::Store
sizeme_graph - Mojolicious app wrapper using Devel::SizeMe::Graph
tests!
Support multiple runs to same sizeme_store process, generating separate files
Name runs to allow total_size (for example) of multiple data structures

Issues:

two cases where PERL_SUBVERSION is checked with a plain || (marked XXX)

Future

Add addr to leaf to enable visualization of memory layout

Add token for ptr to node already seen (identified by addr I presume)
    so we can move from a Tree to a DAG and see alternative name paths
    and reference loops