Re: [PATCH] shrink per_cpu_pages to fit 32byte cacheline

Arjan van de Ven
2004-09-14T11:13:29Z

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On Tue, Sep 14, 2004 at 06:34:07AM -0300, Marcelo Tosatti wrote:
> How come short access can cost 1 extra cycle? Because you need two "read bytes" ?

on an x86, a word (2byte) access will cause a prefix byte to the
instruction, that particular prefix byte will take an extra cycle during execution
of the instruction and potentially reduces the parallal decodability of
instructions....

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