Re-checking disk cache

Today I had a rather spectacular system crash.
I quickly recovered (God Bless ReiserFS), but then
after a while my squid CPU usage shot up to 100%,
and I got messages of "WARNING: swapin MD5 mismatch".
But the cache sort of worked, so I left it run.

Now at business-day-end, I was able to shut down
squid and restart it to double-check the disk caches.
Lots of objects are broken, it's taking forever.

This got me thinking. How hard would it be to
implement an option to force a disk cache re-check while
the cache is live? (read: could pretty please somebody
do that?)

And then some more: I'm using Linux, and I'm an happy
diskd user. I've heard voices of aufs being potentially faster
on Linux, but I can't use it, the SIGUSR* would be
lost and I _need_ logfile rotation.
How hard would it be to implement some other scriptable
control interface? For instance, a named pipe would be
quite OK with squid's overall model, and it would cost only
one FD.

-- 
	/kinkie