device polling problem with the bge(4)

MQ antinvidia at gmail.com
Sat Nov 4 04:51:43 UTC 2006


Hi,
I have two boxes running bge(4). One is ARIMA SW330 with two 5780 on board,
another is HP NC6000 notebook with 5701. After I enabled device polling, I
found the lost_polls is always increasing. I looked through the codes in
/sys/dev/bge/if_bge.c, and finally found that the problem lies in the
function bge_tick. More exactly, the problem is caused by mii_tick. It is
called frequently, and normally returns in 0.5ms. But it always get one
chance to cost 4~5ms in every 4s.

This behavior causes the BGE_LOCK statement in bge_poll() to delay 4~5ms,
and finally makes the lost_polls increasing. Additionally, the HZ for
bge(4), at least  for my bge(4) cards, is limited to at most 2000, or there
will be lost_polls every second. I hope this is a fixable problem, and fixed
soon.


Thanks.


More information about the freebsd-net mailing list