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Date: Mon, 07 Jul 2003 21:32:53 +1000
From: Nick Piggin <piggin@cyberone.com.au>
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To: Con Kolivas <kernel@kolivas.org>
CC: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Process scheduler fairness bug (feature?)
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Hi Con,
In recent testing unrelated to your interactivity stuff,
I have found the following with 74-mm2, although I don't
think its due to your interactivity stuff.

I don't have a real workload that is bothered by this btw.
Just wondering if its fixable, or there is a reason for it.

On UP, 2 processes of same priority. One is doing an
infinite loop of nothing, the other doing an infinite loop
of fork+waiting for children which count to a million then
exit (do a bit of work).

The non forking CPU hog gets 75% of the cpu.