Re: kern.boottime drift after boot?

[RVP <rvp%SDF.ORG@localhost>]

On Wed, 11 Oct 2023, Simon Burge wrote:

> RVP wrote:
>
> > I think what David's looking for is something akin to Linux's
> >
> > /proc/sys/kernel/random/boot_id
> >
> > something which only changes on every boot but is otherwise stable.
>
> I'm curious how well this boot_id works on Linux for things like a
> embedded system (eg router) that boots from a ram disk and doesn't have
> an RTC.  Essentially a similar problem to our long-running entropy
> discussion.

On embedded systems without an RTC, you _could_ get the same UUID in rare
cases. But I think this would be a bug, because on Linux, any kind of jitter-
source (interrupt timing, for instance) would perturb the generated UUID.

-RVP