Aggregate network interfaces

John-Mark Gurney gurney_j at resnet.uoregon.edu
Fri Aug 26 05:53:47 GMT 2005


Dave+Seddon wrote this message on Fri, Aug 26, 2005 at 12:32 +1000:
> - Gig cards are cheap.

yep... $25 for a card, and $100 will get you a 8 port switch that will
do jumbo frames (MTU sizes of 9000 and more instead of the default
1500)...  and you can even use the same wiring, no need for cat5e, cat5
works just fine for gige (as long as you wired all four pairs through)...

> - PCI bus throughput is really bad (like 32MB/s)

nope, PCI raw bandwidth is 133MB/s...  33.3mhz * 4 bytes/cycle, though some
of that is lost to command overhead, but you can do 100MB/s on PCI if
the bridge doesn't interrupt your card too much...  The usual problem
is that the PCI bus bandwidth is shared with your HD, so you'll use
50MB/sec reading from your HD, and then the other 50MB/sec out the
gige.. (if you're lucky)..

-- 
  John-Mark Gurney				Voice: +1 415 225 5579

     "All that I will do, has been done, All that I have, has not."


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