GigE Performance Comparison of GMAC and SUNGEM Drivers

Benjamin Herrenschmidt benh at
Wed Nov 21 12:25:57 EST 2001

>As a result GEM sends pause frames when there is even the slightest
>amount of DMA traffic is has to compete with.  On a 33Mhz/32-bit PCI
>bus, it is sending pause frames all the time even if it is the only
>agent making use of the bus.

Ok. At least, the UniNorth version runs on a 66Mhz bus directly
hooked to the CPU bus within the north bridge. The only other device
sharing that PCI segment is FireWire (well, it's a bandwidth hog
too be more rarely used so far).

Thanks for the clarification.


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