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SubjectRe: memcpy_toio on i386 using byte writes even when n%2==0
Date
Followup to:  <447CE99B.7070707@shaw.ca>
By author: Robert Hancock <hancockr@shaw.ca>
In newsgroup: linux.dev.kernel
> >
> > Note that there isn't any code for moving dwords because the
> > chances of gaining anything are slim (alignment may hurt).
>
> I'd say the chances of gaining something from executing half as many
> instructions on copying a large block of memory are very good indeed..
>

For something that generates I/O transactions, it's imperative to
generate the smallest possible number of transactions. Furthermore,
smaller than dword transactions aren't burstable, except at the
beginning and end of a burst.

-hpa

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