Andrew Gallatin wrote: > > On other OSes, (freebsd, linux) transmits are copied into buffers > which are nicely aligned to page boundaries, and the DMA descriptor > chains may have tiny segments at the front or rear, but > never in the middle, as seems to be the case in Solaris. >
FWIW I see the same sort of arbitrary fragmentation patterns on Windows as I do on Solaris; the advantage with Windows is that the memory has already been DMA mapped by the system and so there's no overhead of deciding whether to DMA map or copy in the driver (since copying short fragments into better aligned pre-allocate DMA buffers is usually lower cost). I think the Linux/FreeBSD stacks are just kinder to drivers :-) Paul _______________________________________________ networking-discuss mailing list [email protected]
