I asked about this on the fedora devel list:
http://www.redhat.com/archives/fedora-devel-list/2007-October/msg02324.html
I don't think the kernel should worry about this.
I don't even think distros should change the default settings of the BIOS/disk.
Up to and including Fedora 7 on my laptop, the disk did a load cycle
on average once every 48 seconds. Mounting the filesystems noatime changed this
to once every 108 seconds, which is a little aggressive still but not too bad.
Note fedora 8 will have the relatime option on by default for all filesystems.
Pádraig.
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