Manuel Bouyer wrote:

> On Apr 20, Al Urbaitis wrote
>
> Hum, wait a minute ... Why would the CPU speed get involed here ?
> If I understand it correctly, the FIFOs are filled with bus-master DMA
>
> transfers, aren't they ? If this is correct, this means that the DMA
> operation
> was not quick enougth. So there is something else that blocks DMA
> operation,
> and I don't think this can be the CPU ...
> I've just seen these kind of message on my PPro-200 with a 100Mb
> board,
> doing a large file copy. This host also have a aha2940 with an UW
> drive.
> Ethernet DMA may have been slowed down because of aha2940 tranfers.

I took a closer look at the machine and noted that the problem seems
toappear on those ports that happen to share an interrupt with the 2940
card.

de0 and the 2940 share IRQ 11.

de2 seemed to run fine all by itself on IRQ 9.

I am not to familiar with the vagaries of interupt sharing ... would
someone shed
some light :-)




Al Urbaitis
Image Guided Surgery
Picker International
Albuquerque New Mexico
505-480-5163
aurbaiti@servecom.picker.com