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SubjectRe: memcpy_toio on i386 using byte writes even when n%2==0
H. Peter Anvin wrote:
> 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.

Well, theoretically for writes they could be, if the memory region was
prefetchable and the PCI chipset supported byte merge. It certainly
isn't optimal however.

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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