perldoc LWP::UserAgent |grep -i cach
File STDIN:
           conn_cache              undef
        a "LWP::ConnCache" is set up (see conn_cache() method below). 
+The
        for the connection cache. The "keep_alive" option also has the
    $ua->conn_cache([$cache_obj])
        Get/set the *LWP::ConnCache* object to use.
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See, no caching is done.