Nabeel Ahmed a écrit : > Hi All, > > I'm wondering if someone can provide me some hints to tackle a problem > I've been hitting my head on for the last couple of days. I've been > working with the ath5k code for the last couple of weeks and am running > into some performance issues with the driver. > > My problem involves scheduling packets at precise time intervals, as a > means to synchronizing the operation across two wireless nodes. I'm > using high resolution timers with the 2.6.31 kernel to allow kernel > scheduling with accuracies of up to 5-10microseconds. This works really > well with respect to scheduling packets in the ath5k driver. However, > once the packets are handed over to the hardware (using DMA), every so > often, packet transmissions get delayed (adding anywhere from 100-3000us > to the expected transmission time). I'm not sure why this might be > happening. To isolate the impact of the wireless channel (i.e., to > ensure that a busy medium is not the cause), I disabled carrier-sense > and increased the noise floor to 0. However, this did not have much of > an effect. My hunch is that some operation in the hardware is > introducing these unpredictable delays. Has anyone experienced this > problem with the driver? I'm using the latest version of ath5k with the > AR5212 chipset. My kernel version is 2.6.31-14. > > I would greatly appreciate anyone's feedback on this issue. > > Thanks a lot in advance! > > Nabeel. > Did you disable virtual carrier sense as well ?
Regards, Benoit _______________________________________________ ath5k-devel mailing list ath5k-devel@lists.ath5k.org https://lists.ath5k.org/mailman/listinfo/ath5k-devel
