A
disk caching strategy:
when an
application reads a block from a
file,
and unless the
I/O subsystem has reason to believe that the application is reading the file other than
sequentially,
a
proactive read of the
next block is automatically
scheduled, meaning that when the application asks for it, it'll probably be in the
cache already.
If you have an I/O cache at all,
readahead is easy to implement,
and gives you good bang for the buck.