| Subject: | Memory leak caused by parent relationships |
| Date: | Tue, 11 Sep 2007 12:37:06 +0200 |
| To: | bug-XML-RSS-Parser [...] rt.cpan.org |
| From: | Kjell-Magne Øierud <kjellm [...] linpro.no> |
I have found memory leaks in this module. You can use the script
included below to verify this. The script uses Devel::Leack::Object
to track object creation and destruction.
By parsing the same feed several times and for each iteration report
tracked objects that still are alive, you can see the object counts go
up for each parsing. By also using Devel::Cycle (uncomment the two
relevant lines in the script) you can also see that this is caused by
cycles in the feed data structure. These cycles are created because
each node has a reference to its parent.
I have found that by breaking all the parent relationships, the memory
leak goes away.
My System:
* XML-RSS-Parser-4.0
* This is perl, v5.8.8 built for i486-linux-gnu-thread-multi
* Linux foo 2.6.20-16-386 #2 Fri Aug 31 00:51:58 UTC 2007 i686 GNU/Linux
* Ubuntu/Edgy
Regards,
Kjell-Magne Øierud
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#!/usr/bin/perl
use warnings;
use strict;
#use Devel::Cycle;
use Devel::Leak::Object 0.90 qw( GLOBAL_bless );
use XML::RSS::Parser;
sub delimit { print '-'x78, "\n" }
my $raw_feed = join "", (<DATA>);
for (1..5) {
if ($_ > 1) {
delimit();
Devel::Leak::Object::status();
}
my $feed = XML::RSS::Parser->new()->parse_string($raw_feed);
#find_cycle($feed);
}
delimit();
__DATA__
<?xml version="1.0"?>
<rss version="2.0">
<channel>
<title>Foo Bar</title>
<link>http://example.com/</link>
<description>Foo Bar</description>
<language>en-us</language>
<item>
<title>Lorem ipsum dolor sit amet</title>
<link>http://example.com/395852</link>
<description>
Lorem ipsum dolor sit amet, consectetuer adipiscing
elit. Fusce non felis in ligula dictum porta. Vestibulum at
velit. Donec eros odio, congue in, consequat in, euismod sed,
nibh.
</description>
<pubDate>Tue, 10 Jun 2003 04:00:00 GMT</pubDate>
</item>
<item>
<title>Duis vestibulum risus id lorem.</title>
<link>http://example.com/395878</link>
<description>
Cum sociis natoque penatibus et magnis dis parturient montes,
nascetur ridiculus mus. Quisque consequat.
</description>
<pubDate>Tue, 10 Jun 2003 07:00:00 GMT</pubDate>
</item>
</channel>
</rss>
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