On Tue, 2005-08-16 at 11:25 -0700, Christoph Lameter wrote: > You mentioned that the NTP code has some issues with time interpolation > at the KS. This is due to the NTP layer not being aware of actual time > differences between timer interrupts that the interpolator knows about.
My understanding of the issue was that when NTP makes an adjustment, it only affects xtime, and any difference between the adjusted time and the interpolator's time was just accumulated in the interpolator's offset. That then, to my understanding, required the bit about adjusting the interpolator frequency to be slower then what we expect so negative offsets can be applied. Looking at it closer, it may very work, but it does seem to be addressing the issue somewhat indirectly. > If the NTP layer would be aware of the actual intervals measured by the > timesource (or interpolator) then presumably time could be adjusted in a > more accurate way. This is basically what I do in my patch. I directly apply the NTP adjustment to the timesource interval, and periodically increment the NTP state machine by the timesource interval when we accumulate it. thanks -john - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/