Re: memcpy_toio on i386 using byte writes even when n%2==0

[Robert Hancock]

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
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Home Page: http://www.roberthancock.com/

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