GigE Performance Comparison of GMAC and SUNGEM Drivers

Benjamin Herrenschmidt benh at
Tue Nov 20 23:02:32 EST 2001

>I'd consider it much more than nice.  Since the whole point of GigE
>is better performance, taking such a huge peformance/CPU hit would
>be extremely bad.  OTOH, I probably won't be using the built-in GigE
>hardware anyway because of its apparent performance ceiling of about
>660 Mbps and its lack of jumbo frame support.

Well, I think we may get overall better perfs once we have this
fixed, and (David, can you confirm ?), I think jumbo frames can
be supported.

So there is a small issue with the Tx ring that I'll fix asap
but it doesn't explain your problem, you are getting way too
much interrupt, possibly those rxmac/txmac interrupts I've noticed

I'll investigate a bit and send you a patched driver.

Thanks for taking the time for testing,


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