[Info-vax] clock problems with OpenVMS x86 on VirtualBox

[David Jones]

On Monday, May 15, 2023 at 4:37:47 PM UTC-4, Dan Cross wrote:
> In fairness to your laptop, it probably has a very good clock. 
> Drift of the kind discussed in this thread would take place over 
> days or weeks, not just hours. 
> 
> - Dan C.

For connecting to my Raspberry Pi's, I bought a cheap PCF8523 RTC
($7) and a better DS3231 RTC ($25), the better one being accurate to
3 seconds per month. A drift of 100ms per day can be detected over
12-18 hours or less. What incentive do they have to put a super
accurate clock in a computer they expect to be on the network and
talking to time servers?

Why did I buy an RTC for my Pi? I'm doing data collection with it and
Pi's don't have an RTC on the card. If it boots after a power outage,
there is a window where timestamps will be wrong because it starts
the system time at the last checkpoint and runs with that until it can
get a correct time from either an NTP source or an external clock. I
have a cron job that syncs the RTC with an NTP source every 10
days.