> Most web servers TCP slow start algorithm starts by sending 10 TCP packets. Of course big names that run CDNs have fancy custom stuff that directly puts data

> Most web servers TCP slow start algorithm starts by sending 10 TCP packets. Of course big names that run CDNs have fancy custom stuff that directly puts data into mmaped regions for the network card to use, but generally, it's the OS handling TCP connections, and this means that the web server, a user space process, only interacts with the TCP connection through a streaming API. It can't issue individual TCP packets or ACK packets or anything. Raw socket access requires superuser privileges in unix. Outside of that it's a great article. Didn't know about this particular trick :).