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Date: Mon, 16 Aug 2004 06:26:53 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Lee Revell <rlrevell@joe-job.com>
Cc: Florian Schmidt <mista.tapas@gmx.net>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       Felipe Alfaro Solana <felipe_alfaro@linuxmail.org>
Subject: Re: [patch] voluntary-preempt-2.6.8.1-P0
Message-ID: <20040816042653.GA14738@elte.hu>
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* Lee Revell <rlrevell@joe-job.com> wrote:

> > > just to check this theory, could you make __check_and_rekey() an empty
> > > function? This should still produce a working random driver, albeit at
> > > much reduced entropy. If these latencies have a relationship to the
> > > mlockall() issue then this change should have an effect.
> > 
> > hm, could you disable the random driver in the .config rather? It seems
> > that adding to the entropy pool (from hardirq context) alone is quite
> > expensive too.
> > 
> 
> Can this be disabled in the .config?  I can't find an option for it.

oh well, indeed it cannot be disabled. Then i'd suggest to return early
from extract_entropy(), without doing anything. That is the function
that seems to introduce the worst overhead.

	Ingo