From owner-freebsd-hackers@FreeBSD.ORG  Wed Aug 31 11:39:45 2005
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Subject: RE: IBM Active Protection System Approach
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> what would be the best approach to implement aps on FreeBSD?

> We have to poll the device for information quiet often to detect a
possible shock early enough to park disk drive heads.

> Would an daemon be sufficient for that? Reaction time? What about an
kernel thread?

sorry for being that late on this, but just a thought:
shouldn't this be an issue for the hdd-vendors to put
this kind of protection algorithm directly into their
hdd-controller-firmware? also, the accel.-detection
could be on the hdd, not inside the nb.
couldn't this save time and programming efforts for
parking, flushing or even stopping the heads/plates?
what about some kind of electronic "brake" that immed.
stops the rotating plates in case of detection of such
an event?
cu...
ps: just reply to the list, i'm on it!