Background block scrubbing

Robert Krten root at
Wed Apr 27 12:18:34 PDT 2005

I don't know where to ask but here :-)

Is there a utility that does background unused block scrubbing?

What I'm thinking of is something that looks for unused blocks on the
disk, and then writes zeros, then random, then more random, etc, to them
for security applications.

It would need to have some cooperation from the filesystem so that it could
lock down a block (or ten, or some number) at a time that it could then go
and "scrub" during idle periods...  Since it would only allocate a few
blocks at a time, it wouldn't need to have a mechanism to release them (IMHO).

If there's nothing like it, can anyone give hints on where I should look in
the source tree for an appropriate place to put such a thing?

Thanks in advance!


Robert Krten, PARSE Software Devices +1 613 599 8316.
Looking for Digital Equipment Corp. PDP-1 through PDP-15 minicomputers!

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