On Sat, 21 Mar 2015 16:23:30 -0000 "David J Taylor" <[email protected]> wrote:
> I've just put up my first draft of a comparison of these two popular devices > as NTP servers: > > http://www.satsignal.eu/ntp/BBB-vs-RPi.html > > Comments welcomed - I know it's an imperfect test! Something is wrong here. I would expect the BBB to perform at least as well as the rpi (after all, the BBB has an ethernet MAC with IEEE1588 support, while the rpi is basically a glorified USB controller with attached graphics card). You are most likely running services on the BBB (network services, local services, cron jobs,...) that cause the high, and spikey cpu load, which in turn destroys your ntp performance. Also, compare your results to [1], where Dan Drown uses the capture/compare unit of the AM3359 to timestamp the PPS and use this for ntp. In [2] he tries to measure the temperature dependence of the BBB oscillator (not be best way, but...). Attila Kinali [1] http://blog.dan.drown.org/beaglebone-black-timer-capture-driver/ [2] http://blog.dan.drown.org/tcxo-beaglebone-black/ -- < _av500_> phd is easy < _av500_> getting dsl is hard _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
