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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Mon, 13 Sep 2010 09:36:56 -0700
Message-ID: <AANLkTimB9CjH5SjeY9XmwhTp1tfFPwh-Q1Y4o918h7XD@mail.gmail.com>
Subject: Re: [RFC PATCH] check_preempt_tick should not compare vruntime with
 wall time
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>, LKML <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
        Steven Rostedt <rostedt@goodmis.org>,
        Thomas Gleixner <tglx@linutronix.de>, Tony Lindgren <tony@atomide.com>,
        Mike Galbraith <efault@gmx.de>
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On Mon, Sep 13, 2010 at 9:16 AM, Mathieu Desnoyers
<mathieu.desnoyers@efficios.com> wrote:
>
> OK, the long IRC discussions we just had convinced me that the current scheme
> takes things into account by adapting the granularity dynamically, but also got
> me to notice that check_preempt seems to compare vruntime with wall time, which
> is utterly incorrect. So maybe all my patch was doing was to expose this bug:

Do you have latency numbers for this patch?

                    Linus