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Date: Thu, 5 Jun 2003 01:15:47 +0200
From: Ralf Baechle <ralf@linux-mips.org>
To: Jun Sun <jsun@mvista.com>
Cc: linux-mips@linux-mips.org
Subject: Re: [RFC] synchronized CPU count registers on SMP machines
Message-ID: <20030604231547.GA22410@linux-mips.org>
References: <20030604153930.H19122@mvista.com>
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On Wed, Jun 04, 2003 at 03:39:30PM -0700, Jun Sun wrote:

> 1) clocks on different CPUs don't have the same frequency
> 2) clocks on different CPUs drift to each other
> 2) some fancy power saving feature such as frequency scaling
> 
> But I think for a foreseeable future most MIPS SMP machines
> don't have the above issues (true?).  And it is probably worthwile
> to synchronize count registers for them.

1) and 2) affect most SGI systems.

  Ralf