http_ping is like the regular ping command, except that it sends HTTP requests instead of ICMP echo requests.

From acme

-count Stop after the specified  number  of  fetches.   Without  this
       option, http_ping will continue until interrupted.

-interval
       Wait  the  specified  number  of seconds between fetches.  The
       default is five seconds.

-quiet Only display the summary info at the end.