>I've already turned on "noatime, nodevmtime, softdeps" and I still get
>a some disk io every few minutes.  I'm not running whois or anything

Try removing "softdeps" and replace it with "async".  When I ran
with it, it was always writing every few minutes, and I never tracked
down why.

When I was doing the atactl stuff originally, I wrote some code that
printed out the inode and filesystem when a sync() was called to track
down programs that were writing, but I never found the right thing to do
for softdeps.

(I had brought this up a while ago, but no one responded).

--Ken