On Sun, Mar 03, 2019 at 05:59:11PM -0500, Daniel Franke wrote: > On Sun, Mar 3, 2019 at 8:45 AM Kurt Roeckx via devel <devel@ntpsec.org> wrote: > > On Sun, Mar 03, 2019 at 05:23:31AM -0800, Hal Murray wrote: > > > > > > k...@roeckx.be said: > > > > If this is something you're worried about, this can be solved with the > > > > interleave mode, which was removed. > > > > > > How well does it work? > > > > It works great, the errors are much smaller when it's enabled. > > Interleaved mode in NTP Classic doesn't do what you think it does. > > The concept behind interleaved mode is sound: get packet timestamps > from the NIC at the moment they cross the wire, thus eliminating the > contribution of local buffers to jitter. But ntpd doesn't do anything > of the kind! > > Actually getting timestamps from the NIC is fairly involved. The NIC > has its own clock and its own oscillator, which has to carefully be > kept in sync with the system clock. Furthermore, all the APIs for > doing this are OS-specific. Check out the linux-ptp project to see > what it looks like when it's done right; it's a fair bit of code, and > nothing of the kind is present in ntpd.
But it is present in chrony. It supports both interleaved mode and hardware timestamping. Kurt _______________________________________________ devel mailing list devel@ntpsec.org http://lists.ntpsec.org/mailman/listinfo/devel
