Re: PSA: Clock drift and pkgin
Mouse <[email protected]>
| Newsgroups | gmane.os.netbsd.ports.vax |
|---|---|
| Message-ID | <[email protected]> |
>> But a drift of a couple of % would not be unexpected. > Um, yes, it would be unexpected. > The crystal spec in that era was 0.01%, [...] > If you see a couple % drift, that's definitely not the crystal. I'm not so sure. My experience is that older machines keep worse time than newer ones, even high-quality older machines and cheapo newer ones. I suspect that crystal frequencies drift with time (or perhaps with something that tends to correlate positively with time, such as wide temperature ranges in storage). And, whatever the cause, I don't find a couple of percent drift surprising in practice. I once had a machine (I forget what kind) that had really good timekeeping, just not at the frequency it was supposed to - exactly what I would expect if the crystal were something like 5-10 percent out of spec. I had to manually fudge NTP's drift value to something _way_ out of the normal drift range, but, once I found a close-enough starting value that NTP settled down and refined the drift setting, it kept good solid time. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML [email protected] / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B