Again, just use LWP (and possibly Time::HiRes if you want finer than second granularity).

use LWP::Simple qw( get );
use Time::HiRes qw( time );

my $url = "http://...";

my $start = time;
getstore( $url, "/dev/null" );
my $end = time;

print "Took ", $end - $start, " seconds\n";
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