On 2011-04-19, David Lord <[email protected]> wrote: > unruh wrote: >> On 2011-04-19, David Lord <[email protected]> wrote: >>> David J Taylor wrote: >>>> "unruh" <[email protected]> wrote in message >>>> news:[email protected]... >>>> [] >>>>> Well, I think someone other than the current maintainers will have to >>>>> port it to windows. Since windows timekeeping is not the worlds best >>>>> anyway, it is probably true that the extra accuracy of chrony is >>>>> unnecessary. It does have a command line option "like ntpq -p" >>>>> provided by chronyc (depending on what you mean by "like"). >>>>> What MRTG is I do not know. >>>>> >>>>> If you are happy with ntpd, by allmeans stay with it. >>>> A pity that chrony will not be offered for Windows, at least for tests >>>> to see whether it lives up to its claims. There are times when a more >>>> rapid convergence would be welcome, such as the reboot of PC Molde >>>> around 13:30 yesterday: >>>> >>>> http://www.satsignal.eu/mrtg/molde_ntp-b.html >>>> >>>> MRTG is a standard logging tool for network I/O which uses SNMP to >>>> produce the graphs I have quoted here many times for network throughput >>>> and timekeeping: >>>> >>>> http://www.satsignal.eu/mrtg/performance_network.php >>>> http://www.satsignal.eu/mrtg/performance_ntp.php >>>> >>>> I've written how to extend MRTG to monitor NTP timekeeping, and various >>>> other parameters such as disk space and temperature here: >>>> >>>> http://www.satsignal.eu/ntp/NTPandMRTG.html >>>> http://www.satsignal.eu/mrtg/performance_howto.php >>>> >>>> From chronyc I would need to be able to use a simple Perl script to >>>> extract the numbers to be plotted - such as the Offset in the graphs >>>> above. An easy job if the format is standardised and machine readable. >>> I based my script on yours for ntp but changed from using a >>> linear axis to log. I first used chrony on NetBSD when on >>> dialup with demon and later for a while when on broadband. >>> When I first compared chrony with ntpd there was no contest >>> but more recent experiments with chrony had periods of >>> severe instability much worse than ntpd. >> >> More recent means what? What version of chrony? (there was a bug found >> in the past two weeks that was introduces a few months ago which did >> result in instability) > > More recent than November 2009. > Probably between Dec 2009 and Jan 2010 and p4x2400c. > > chrony 1.23
OK well before that change. > > >>> P4X2666 with chrony >>> <http://www.lordynet.org.uk/mrtg/stats/> >> >> Not at all sure what I am supposed to see. I have no idea what the graph >> axes represent? What is 1.1k > > X-axis is in hours > Y-axis is offset in us so 1.1k = 1100us WOW. What kind of network are you attached to? Even on an ADSL link through the phone company, I was getting in the tens of usec (not ms) as the offsets of chrony. (checked by a gps receiver attached to the local computer). And what is it about the graph that makes you believe you are seeing instability. > > Next experiment is to couple up the GPS again but if you > click on the ME6000 in the current stats the yearly graph > for Sep/Oct/Nov was when I last had the gps connected. > > > David > >> Note that you can see my offsets with chrony on my web page. The network >> problems really do cause difficulty, but the offsets in general are very >> small -- 10usec over the network. >> >> >>> Current stats all with ntpd. >>> <http://www.lordynet.org.uk/mrtg/stats/ntp/> >>> >>> >>> David >>> _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
