4 ms·
Not an expert but this doesn't seem like normal ping, it's rather how much HTTP request take including handshakes and content download
by vdfs 4y ago
Not an expert but this doesn't seem like normal ping, it's rather how much HTTP request take including handshakes and content download
- netsharc 4y agoI wonder if it could be done better using WebSockets: setup the connection, start the stopwatch, send a byte, wait to receive a byte, stop the stopwatch, and close the connection.
- vitus 4y agoNot entirely. Modern browsers / webservers will keep TCP connections alive for at least a few minutes. I ran a tcpdump and confirmed there's only one network round trip involved in the critical path (after the first request, anyhow), with a transfer of a few hundred bytes in each direction (HTTP overhead, but nowhere near big enough to incur processing delays on the same scale as propagation delay). (The actual packets sent: HTTP GET from my end, HTTP response from the server, ACK from my end.) The latency is still 20-40ms higher than ping times, although it's not clear to me whether that's due to disk seek latency, server load, or something else.
- PNWChris 4y agoThis is super helpful context, thank you! I was wondering why the RTTs appeared to converge only after a couple retries, and why the first measurement was so wildly different when pulling up the page after some time away.