Use
s.ping(hostname, port)
Description
Returns the amount of time in milliseconds it takes for your site to contact the given hostname and get a response. If it fails or takes too long, FALSE is returned. Supplying a port is optional and it defaults to 80 if none is given.
NOTE: Keep in mind it takes hostnames and not URLs. Having http://www. will fail.
Example
v.foo = s.ping("codesimplescript.com")
v.bar = s.ping("sbih.co.cc", "8080")