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Date: Tue, 17 Sep 2002 13:39:33 -0700 (PDT)
Message-Id: <20020917.133933.69057655.davem@redhat.com>
To: johnstul@us.ibm.com
Cc: anton.wilson@camotion.com, linux-kernel@vger.kernel.org
Subject: Re: do_gettimeofday vs. rdtsc in the scheduler
From: "David S. Miller" <davem@redhat.com>
In-Reply-To: <1032294559.22815.180.camel@cog>
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   From: john stultz <johnstul@us.ibm.com>
   Date: 17 Sep 2002 13:29:18 -0700
   
   Some NUMA boxes do not have synced TSC, so on those systems your
   code won't work.

It would have been really nice if x86 had specified a "system tick"
register that incremented based upon the system bus cycles and thus
were immune the processor rates.

I foresee lots of patches coming which basically are "how does this
x86 system provide a stable synchronized tick source".
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