8260 Network Performance update

[Allen Curtis]

> link parameters.  You could try increasing the number of receive buffers
> in the Ethernet driver, and I guess we should modify the driver to DMA
> directly into skbufs.  I would be surprised if either of these last two
> would increase the performance, but I've been surprised by a few
> things lately :-).

The table below is performance vs. number of driver buffers. (16 - 64)

			10T Hub	|	100BT switch
		 -------------------------------------|
	16 RTB |	440KBps	|	190KBps	  |
		 --------------------------------------
	32 RTB |	450KBps	|	230KBps	  |
		 --------------------------------------
	64 RTB |	450KBps	|	240KBps	  |
		 --------------------------------------

There is a slight improvement when you increase the number of buffers from
16 (default) to 32. There does not appear to be any benefit beyond that.

I am guessing that the problem is not in the driver unless the driver is
suppose to enforce some soft of fair usage algorithm. Is there a network
usage scheduler of some kind? I do not have this problem on a x86 RedHat
system...


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