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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Chris Friesen <cfriesen@nortelnetworks.com>
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Date: Tue, 19 Oct 2004 09:46:54 +1000
Cc: linuxppc-dev@ozlabs.org
Subject: Re: tbr/decrementer and SMP -- do the cpus stay in sync?
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On Tue, 2004-10-19 at 06:58, Chris Friesen wrote:
> I thought I remembered some discussion on this a while back, but I can't find it 
> in my archived messages or online, so here goes.
> 
> With SMP PowerPC machines (specifically the dual G5) we sync up the timebase 
> when we bring up the second CPU.  Are we guaranteed that they stay in sync after 
> that point, or will they drift?  If they drift, do we have any idea how much?

Yes. They have the same clock source. They won't drift.
Ben.