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Date: Thu, 12 Oct 2006 14:37:13 -0700
From: Andrew Morton <akpm@osdl.org>
To: Akinobu Mita <akinobu.mita@gmail.com>
Cc: linux-kernel@vger.kernel.org, ak@suse.de, Don Mullis <dwm@meer.net>
Subject: Re: [patch 1/7] documentation and scripts
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On Thu, 12 Oct 2006 16:43:06 +0900
Akinobu Mita <akinobu.mita@gmail.com> wrote:

> +- /debug/*/probability:
> +
> +	likelihood of failure injection, in percent.

The fact that this is a percentage worries me.  When I was playing around
with this sort of thing several years ago I found that even
one-failure-per-thousand was a very high error rate for some testcases. 
This interface would force a minimum failure rate of one-per-hundred, which
is terribly high.

So I wonder if it'd be better to make this have units of "one millionth",
or simply make this tunable "1/(probability of failure)".  So setting it to
1,000,000 gives you one failure per million calls, on average.