On Fri, 26 Jan 2001 kuznet@xxxxxxxxxxxxx wrote:
> > Five second transmit timeout. Why is this?
> I would ask: why 400msec? 8)
That was the original value in Don's older drivers. I think that it was
computed based on packet transmission time, inter-packet gap and so on.
But there is a difference: Don didn't have Tx mitigation enabled by
default, so a packet going through would trigger an interrupt which would
clear tbusy and tx_full. With Tx mitigation, for a filled-up ring and
collisions, the interrupt might be delayed past Tx timeout value.
> BTW it really helped to avoid watchdog, when card had some spurious stalls
> due to excessive collisions or those link problems.
Andrew has enabled Tx mitigation by default to reduce interrupt rate
under load. See above.
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