Disk I/O
File system overhead
- file system buffer management not optimal
- don’t need many of the file system facilities
- modifying files, moving files, locking files, seeks…
Alternatives:
- directly interact with disk
- in-memory caching on top of file system
- works well given high locality of server access
- be careful to not suffer from double-buffering
Interaction: thread subsystem and disk
- balanced system - enough threads to saturate disk I/O