$cache_location =~ s/\.[^\.\/]+$//;
# take out a lock on the cache location so that if another request
# is made while we are serving this one, we don't do double work
$cache_location =~ s/\.[^\.\/]+$//;
# take out a lock on the cache location so that if another request
# is made while we are serving this one, we don't do double work