Network I/O
Typical server behaviour rough on network stack
- multiple outstanding connections
- very rapid TCP creation and teardown
- often, very slow last-hop network segment
Redundant operations performed
- checksum calculations, byte swapping, …
Inefficiencies at packet level
- header, body, FIN usually three separate round-trips
Poor network stack implementations
- TIME_WAIT and IDLE PCB entries on single linked list
- Nagle’s algorithm invoked when it shouldn’t be