On Sun, Mar 3, 2019 at 9:44 PM Eric S. Raymond <e...@thyrsus.com> wrote: > (Also, it turns out not to be important at post-Y2K machine speeds to > get those arrival timestamps from the UDP layer ASAP, rather than > looking at packet read time in userspace. The cost of the latter, > naive approach is additional jitter dominated by process-scheduling > time; this used to be significant relative to users' accuracy > expectations for NTP, but scheduler timeslices have since decreased > by orders of magnitude and squashed the issue. We know this from some > tests setup having run for six months with packet-timestamp fetching > accidentally disabled... But they weren't busy systems.)
Scheduler timeslices haven't changed much. The current default on Linux is 1ms and it's been that way for a long time. What's changed is that everybody has multicore processors now, so contention almost never happens. _______________________________________________ devel mailing list devel@ntpsec.org http://lists.ntpsec.org/mailman/listinfo/devel
