Gentoo Virtualbox client clock drifts when guest hibernates

xavier10

I have installed a new Gentoo virtual machine, under Virtualbox on a Mac laptop. However, when I hibernate the guest, the clock of the VM stays where it was (even if I do not hibernate the client). The only solution I found so far is to re-run ntpd, but that is just a workaround. I installed the latest virtualbox-guest-additions.
Not sure what else I could look at.
Any idea ?

Roman_Gruber · Posted: Wed Mar 02, 2016 10:48 am Post subject:

rc-update add ntpd (or what it is called) it will run itself and sync.

in the past some kernels version caused a big clock skew for myself which was fixed later. was on my other notebook and some 3.x.x kernels.

xavier10 · Posted: Wed Mar 02, 2016 9:36 pm Post subject:

Thanks, I tried, but sadly it does not improve the situation.
At startup, it synced the time. Then I did put the host to sleep for one hour, and when I came back, the guest was still at the previous time...
I am confused, on other VMs that I maintain (including an old Gentoo one), this issue does not occur.

Are there some specific options to set into the kernel ?

Thanks!

NeddySeagoon · Posted: Wed Mar 02, 2016 9:40 pm Post subject:

xavier10,

Is it OK when you suspend and restore the entire Virtualbox VM rather than the guest?
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NeddySeagoon

Computer users fall into two groups:-
those that do backups
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szatox · Advocate Joined: 27 Aug 2013 Posts: 3134

Check options regarding emulated real time clock. AFAIR qemu allows you to pick one of 3 or 4 modes, VB can provide similar features. Perhaps changing the mode would let you keep the guest in sync with host.

xavier10 · Posted: Wed Mar 02, 2016 10:01 pm Post subject:

I did some more testing, and clock drift occurs when either of the following occurs:
- the host goes to sleep (with the VM running) which is quite annoying actually, as I do this often;
- I save the VM state and reopen it later;
- the guest goes to sleep...

xavier10 · Posted: Sun Mar 06, 2016 2:43 pm Post subject:

I recompiled a kernel with RTC settings similar to those of some old, well-behaved Virtualbox host, and it does not solve the problem (in particular with HCTOSYS and SYSTOHC off, as in the other system).

Any other idea would be welcome...

xavier10 · Posted: Sat Apr 23, 2016 12:45 pm Post subject:

I have been searching for information on the virtualbox forum, and that did not seem to solve the issue. Some relevant questions arose though.

First, the link to the thread on the virtualbox forum:

https://forums.virtualbox.org/viewtopic.php?f=8&t=76625&p=360052#p360052

Now, it seems the issue is related to the guest additions not functioning properly.
I upgraded the virtualbox executable so that it is at least as recent as the version of the guest additions (we are not supposed to run guest additions newer than a virtualbox executable apparently).
Another thing one poster observed that the version of the guest additions installed by gentoo shows up in the logs with an "OSE" suffix which means it is not a standard version from VB itself, but with some add-ons in the gentoo package so that they cannot help much.

Any feedback would be greatly appreciated...