>> If I were pulling numbers out of the air, I'd call under 10-15 ms "good", >> and under 30-50 ms "tolerable", and beyond that "bad".
> Personally, I would like to see the tolerances increased, but probably > not quite as tight as you are asking for. However, I would much > rather see the problem with the growth rate of clients per server > fixed first. (And, Ask seems to be doing just that, so no complaints > from here about priorities.) Um... did you you mean to write "tightened"? "Increased" tolerances are generally looser. Agreed on priorities, but I've never measured an offset > 20 ms that wasn't due to a configuration problem. General broadband performance is around 2-4 ms in my experience. It seems at least worth *telling* people that things are a little dubious. This is not about kicking people out of the pool, but helping them run good servers. If you don't want to change the current criteria, maybe add a category above "okay" like "really good"? Of course, there are the sympathies expressed in https://fortytwo.ch/mailman/pipermail/timekeepers/2003/000104.html > One of the problems was that Adrian did not have the ability to test > the pool servers from several places around the world. So, if a given > ntp server happened to have bad connectivity to Switzerland, but good > connectivity from the rest of the world, Adrian's scripts could give > your server a bad score. > As a result, the tolerances are very large. IIRC, anything under > 250ms is considered "good". Ah. I usually do it using ntpq to peer servers. Heck, the server itself can usually tell you via ntpq, if any of its peers are sane. Look at 24.172.8.162 for example. It's in the U.S., and most of its problems are that it picked servers in Israel, Poland and Guatemala with 200 ms round-trip times. ntpd knows it has a big offset, it's just so unstable it can't correct it. Pick a couple of reliable NTP servers in each area, have them ping everyone nearbywith minpoll 1024, and you can suck your statistics out of the loop filters. In fact, judging by old mailing list traffic about monitoring servers, that's pretty much exactly how it's done... _______________________________________________ timekeepers mailing list [email protected] https://fortytwo.ch/mailman/cgi-bin/listinfo/timekeepers
