When I run the program below on a Windows XP machine and I watch the memory usage in the Task Manager, the Page File usage climbs steadily with each successive call to get_url. Can anyone point out why, for instance, I start with 887MB and end at 920MB; and as soon as the program completes, it drops back down? Imagine calling thousands of pages and how the memory would continue to expand until you run out.

use strict;
use warnings;
use LWP::UserAgent;
use HTTP::Request;
use HTTP::Response;
use HTTP::Message;

my $ua = LWP::UserAgent->new();
my $iteration = 1;
my $some_directory = 'C:\\';
open(URLS, $some_directory.'urls.txt');
while (<URLS>) {
    my $url = $_;
    chomp $url;
    &get_url($url, $iteration);
    print "($iteration) $url\n";
    sleep 15;
    $iteration++;
}
close URLS;

sub get_url {
    my ($url, $iteration) = @_;
    pipe(READER, WRITER);
    if (my $pid = fork) {
        close WRITER;
        open(FH, '>'.$some_directory.$iteration);
        while (<READER>) {
            print FH;
        }
        close READER;
        close FH;
    } elsif (defined $pid) {
        close READER;
        my $request = HTTP::Request->new("GET", $url);
        my $response = $ua->request($request);
        my $content = $response->content();
        print WRITER $content;
        close WRITER;
        undef $request;
        undef $response;
        exit;
    }
}

[download]

Here's a random sample of urls I have in urls.txt:

http://www.google.com/
http://www.yahoo.com/
http://www.capweek.com/
http://www.autosource1.ca/index.htm
http://www.keithbuickgmc.com/en/
http://www.pawtuckettimes.com/
http://www.stateportpilot.com/
http://www.memphisflyer.com/
http://www.thetelegram.com/
http://www.nugget.ca/
http://highcountrypress.com/
http://www.howstuffworks.com/
http://www.oregonlottery.org/
http://www.springfieldnewssun.com/
http://www.mountvernonnews.com/
http://www.jdnews.com/
http://www.aurorasentinel.com/
http://www.cariddiauto.com/
http://www.enterprise-journal.com/
http://www.naplesnews.com/

[download]

In reply to Memory Leak Caused by Forking? by nwboy74

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