Consequences of HTTP/1.0
Consequences of HTTP/1.0
- Closing connection causes loss of congestion information
- Connection opens may be congesting low bandwidth links, due to lack of flow control on TCP opens and closes
- Poor user perceived performance (most connections in slow-start)
- Workaround has been opening multiple simultaneous connections, with resulting congestion problems
- Servers have thousands of connections in close_wait state
- e.g. AltaVista server is at > 20 million connections/day, or >230/second averaged over 24 hours
- Cost is primarily memory, on systems running reasonable TCP implementations
- Vanity servers with HTTP result in big servers using 100’s of I.P. addresses and consequential routing headaches
- Caching model is primitive, and broken enough that content providers often defeat caching