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Subject: Re: [PATCH] tsc-disable_B9
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Andrea Arcangeli <andrea@suse.de>
Cc: john stultz <johnstul@us.ibm.com>,
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On Thu, 2002-08-15 at 17:56, Andrea Arcangeli wrote:
> sorry but I don't see the point of badtsc only in kernel.
> 
> If the TSC is bad that will be in particular bad from userspace where
> there's no hope to know what CPU you're running on.

You can still do meaningful measurements for things like profiling
because the cpu hop is statistically uninteresting.

> How do you detect the NUMA hw? That would be a nice addition so the
> numa-Q users won't be required to add notsc to the append lilo line.

The current Summit patches from IBM (the ones James did and merged in
-ac) do detection for Numa-Q and Summit. Those are pending for Marcelo
right now so if you have a better way I'd like to know.


Alan

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