unruh <un...@invalid.ca> wrote: > On 2012-06-10, Rick Jones <rick.jon...@hp.com> wrote: > > I'd like to see the full output of ethtool, ethtool -i and ethtool > > -c for your interfaces if I may. Feel free to send as direct > > email if you prefer.
> info:10.0[unruh]>ethtool -i eth0 > driver: e1000 > version: 7.3.21-k8-NAPI > firmware-version: N/A > bus-info: 0000:06:00.0 > info:10.0[unruh]>ethtool -c eth0 > Coalesce parameters for eth0: > Adaptive RX: off TX: off > stats-block-usecs: 0 > sample-interval: 0 > pkt-rate-low: 0 > pkt-rate-high: 0 > rx-usecs: 3 > rx-frames: 0 > rx-usecs-irq: 0 > rx-frames-irq: 0 Might go ahead and set rx-usecs to zero. The Intel drivers have (or at least had) a module parameter called InterruptThrottleRate which tries to be rather clever. http://www.intel.com/support/network/adapter/pro100/sb/CS-032516.htm I'm not sure just at the moment how that shows-up in the ethtool output though. > The fact that the distribution in round trip times is almost a > perfect square pulse (Ie, constant probability between the minimum > 1.4us to the max .4us) suggests that may it is polling rather than > interrupt, altough the card certainly has an interrupt At this stage in the Linux kernel I don't believe that NAPI can be disabled. I believe it switches over to polling only after some threshold though. Pehaps mentioned in the previous URLs. rick jones -- The glass is neither half-empty nor half-full. The glass has a leak. The real question is "Can it be patched?" these opinions are mine, all mine; HP might not want them anyway... :) feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH... _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
