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Subject: Re: Prezeroing V2 [0/3]: Why and When it works
From: Arjan van de Ven <arjan@infradead.org>
To: Christoph Lameter <clameter@sgi.com>
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> The most expensive operation in the page fault handler is (apart of SMP
> locking overhead) the zeroing of the page. This zeroing means that all
> cachelines of the faulted page (on Altix that means all 128 cachelines of
> 128 byte each) must be loaded and later written back. This patch allows to
> avoid having to load all cachelines if only a part of the cachelines of
> that page is needed immediately after the fault.

eh why will all cachelines be loaded? Surely you can avoid the write-
allocate behavior for this case.....