Re: Van Jacobson's net channels and real-time

[Robert Hancock <hancockr@shaw.ca>]

linux-os (Dick Johnson) wrote:
> Message signaled interrupts are just a kudge to save a trace on a
> PC board (read make junk cheaper still). They are not faster and
> may even be slower.

Save a trace on the PC board? How about no, since the devices still need 
to support INTX interrupts anyway. And yes, they can be faster, mainly 
because being an in-band signal it simplifies some PCI posting related 
issues, and there is no need to worry about sharing.

 > They will not be the salvation of any interrupt
> latency problems. The solutions for increasing networking speed,
> where the bit-rate on the wire gets close to the bit-rate on the
> bus, is to put more and more of the networking code inside the
> network board. The CPU get interrupted after most things (like
> network handshakes) are complete.

You mean like these?

http://linux-net.osdl.org/index.php/TOE

-- 
Robert Hancock      Saskatoon, SK, Canada
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