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Subject: Re: [PATCH v4 2/2] add icswx support
From: Benjamin Herrenschmidt <benh@au1.ibm.com>
To: "Tseng-Hui (Frank) Lin" <thlin@linux.vnet.ibm.com>
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Date: Sat, 05 Mar 2011 10:13:59 +1100
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On Fri, 2011-03-04 at 17:07 -0600, Tseng-Hui (Frank) Lin wrote:
> I don't have any measurable numbers. That's why I made it an option in
> case people wants to disable it. I do agree that the kernel has so many
> options that we should refrain from adding more. If the chance that the
> lazy switching slows down the execution is really low, we should just
> take out the option. Is there any one has an idea how much the numbers
> are? 

Well, per-cpu loads are notoriously inefficient due to nasty codegen,
but often cache hot as well, I wouldn't worry too much. Just remove the
option for now. We can always add it back if it ever becomes desirable,
but I very much doubt it.

Cheers,
Ben.