Another possibility is to not mark inodes dirty just because the atime
field changes. Or mark them dirty in such a way that they don't need to
get written out until the filesystem is unmounted. This would stop
those laptop disks from spinning and probably be Posix compliant too (as
long as the system is running).
Stephen and I talked about doing this very thing at the Berlin Linux
conference. I think this is something you can expect to see in the 2.1
development cycle.
- Ted