On Tue, October 18, 2005 7:03 pm, Michael Kjorling wrote: > So they say, but I'd be careful with running ntpdate from a cron job. > I recall a recent discussion (think it was on [EMAIL PROTECTED], > but could be wrong) where one person was having real trouble because > of it resetting the system clock. When he converted to running ntpd > instead, the problem disappeared. >
Hmm, my guess (somewhat educated) is that ntpdate is abruptly changing the clock, while ntpd normally just slews the clock by adjusting the timer settings. This means that every second on the clock still ticks with ntpd, but not with ntpdate. That probably has a big impact on anything that uses real-time-clock scheduling - especially if you're running ntpdate once a minute or something like that. I'm not sure how multimedia works in linux - it may not use the system clock for timing. If it did I could definintely see issues happening if buffers run out or if video/audio get out of sync. I personally just let leave the RTC on GMT and run ntpd. It is mostly fire-and-forget. As others have pointed out though, it doesn't handle clock slews this large easily (maybe there is a parameter or source-code-constant that can be tweaked to compensate). -- [email protected] mailing list
