file save AND nicing.

[mark%umcp-cs at udel-relay]

From:  Mark Weiser <mark%umcp-cs at udel-relay>

Here is merged response to several recent topics.
We run our whole system file saves multi-user.  After noticing
that they took much longer this way (not too surprising),
we started nicing the dumping program to -18 (pretty heavy priority).
Did this help?  Not very much.  What good is a nice if even
when you are not very nice at all it hardly buys a thing.

The problem is apparently that dump mostly is doing i/o, and somehow
being very negatively nice doesn't help it get buffers and things
fast as it needs them.