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Re:Windows feature that resets system clocks based on random... by toast0 on Wednesday August 16, 2023 @03:29PM (#37152378)
It kind of depends. There's a lot of poor clocks at boot up time, but a continuously running host usually doesn't get too off, too quickly; I've seen some things, but even at 10% fast/slow, you don't have to jump days unless you're checking infrequently.

On the other hand, with virtualization, who knows how long it's really been between clock ticks. Let's say someone suspends a VM for a couple months and then unsuspends it; hopefully the clock is synchronized, but maybe it isn't, and you do need to jump ahead.

I thought I saw in the article that there are failsafes, but the allowed range is still pretty broad. But reporting is going to tend to be dominated by larger values, because smalller jumps are less likely to be noticed or more likely to be considered an accidental change.

Re:Windows feature that resets system clocks based on random... by Wowfunhappy on Wednesday August 16, 2023 @03:40PM (#37152541)
Every VM software I've ever used automatically syncs the guest OS's clock to the host OS's clock. I've never used VMs in a server context, but do servers not do this too? It seems like the logical solution here.
Re:Windows feature that resets system clocks based on random... by toast0 on Wednesday August 16, 2023 @04:17PM (#37153122)
I've certainly had issues with time sync in the past, and Windows has a wide range of deployment, so I would imagine they can't rely on it.