In message: <[EMAIL PROTECTED]> Darren Pilgrim <[EMAIL PROTECTED]> writes: : "M. Warner Losh" wrote: : > : > In message: <[EMAIL PROTECTED]> : > Darren Pilgrim <[EMAIL PROTECTED]> writes: : > : If you're really worried about it, get a GPS device that can provide : > : you with a PPS signal for use with ntpd. Then I'd say you could safely : > : rely on the computer's clock being accurate. : > : > If you are lucky enough to find "accuracy" in the 10s of us close enough. : : I don't quite understand what you're saying here.
I'm saying that ntp steers the system clock only +- 40-70us (eg a few 10's of us) in the best client situation on a LAN. Reference clocks can get the system time deviation down to a few microseconds (on the order of 2-5us). phk claims to have gotten better with custom clock hardware... of course these numbers are from FreeBSD 4.3 and the ntp nano-kernel in the kernel has gotten a little better since then. Warner To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
