my $xml = getXML($url); # retrieve it thru http
my $parser = new XML::DOM::Parser;
my $doc = $parser->parse($xml);

# This first snippet would take as much as 2Gigs of memory. 

##</code><code>##

my $xml = getXML($url); # retrieve it thru http
my $file  = writeToFile($xml) or return; 
my $parser = new XML::DOM::Parser;
my $doc = $parser->parsefile($file);

# This isn't even noticeable