> Do you include Sun (now Oracle) Solaris in the list of "others"? I ask > more out of interest than anything else, but a large proportion of the > machines here run Solaris. The only two machine that run 24/7, run > Solaris. > > I've got machines here running CentOS Linux, Solaris (SPARC), Solaris > (x86), OpenSolaris (x86), AIX (PowerPC), HP-UX (PA-RISC), Windows 7, > 32-bit Windows XP, 64-bit Windows XP .. plus any I forgot. I used to > have tru64 and IRIX too, but decided they were a bit old hat.
What is your goal for accuracy? NTP can be as good as about 2 uSec if you do everything following best practice. But you can also use a USB connected GPS with an indoor antenna and MS Windows for the server and get in the "handful of milliseconds" range. That would be three orders of magnitude worse but still good enough for most uses. One of the conciderations is how well (and if) the pulse per second driver is implemented. Ideally this would be about 12 lines of code in the interrupt handler. The last time I used SPARC for an NTP server it was a 32-bit CPU running SunOS in the pre-solaris days. Si it was BSD based. It worked well. If you want help it would be best to use linux or BSD running on an Intel CPU. On that arthitectue the DCD pin on the serial port is tied to an interrupt controller and it is very simple Power is a bigger issue. It really does cost a bit to keep some machines owered up 24x7 and NTP needs to run all the time. It takes NTP hours to stabilize and you want to wait 24 hours after to measure performance. If you don't need the frquency standard all the time you might use a lower powered GPS for NTP. THere are many good ones. I have a couple Moterola "UT+" units I got for $18 each. These output a PPS with 1 sigma error under 100 nanoseconds, better than NTP can use. The UT+ is tiny, credit card size. t-bolts use more power because of the OCXO heater. Chris Albertson Redondo Beach, California _______________________________________________ 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.
