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Date: Sat, 14 Apr 2007 12:55:56 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Daniel Walker <dwalker@mvista.com>
Cc: linux-kernel@vger.kernel.org,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Con Kolivas <kernel@kolivas.org>, Nick Piggin <npiggin@suse.de>,
       Mike Galbraith <efault@gmx.de>, Arjan van de Ven <arjan@infradead.org>,
       Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]
Message-ID: <20070414105556.GC19454@elte.hu>
References: <20070413202100.GA9957@elte.hu> <1176502546.3129.79.camel@imap.mvista.com> <20070413223017.GA8961@elte.hu> <1176508785.3129.89.camel@imap.mvista.com>
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* Daniel Walker <dwalker@mvista.com> wrote:

> One other thing, what happens in the case of slow, frequency changing, 
> are/or inaccurate clocks .. Is the old sched_clock behavior still 
> tolerated?

yeah, good question. Yesterday i did a quick testboot with that too, and 
it seemed to behave pretty OK with the low-res [jiffies based] 
sched_clock() too. Although in that case things are much more of an 
approximation and rounding/arithmetics artifacts are possible. CFS works 
best with a high-resolution cycle counter.

	Ingo