Opened 16 years ago
Closed 14 years ago
#4837 closed defect (fixed)
Linux guest clock skew problems go away with nohz=off
| Reported by: | Robin Smidsrød | Owned by: | |
|---|---|---|---|
| Component: | documentation | Version: | VirtualBox 3.0.4 |
| Keywords: | nohz, nohz=off, tickless, timer | Cc: | |
| Guest type: | Linux | Host type: | Windows |
Description
The user faq states that setting nohz=off should not be necessary after virtualbox 1.6.
I'm running VirtualBox 3.0.4 on a Vista x64 host with a Ubuntu 8.04 server 32bit guest, and I had make clock skew problems consistently.
Setting nohz=off made it go away.
Change History (4)
comment:1 by , 16 years ago
| Summary: | User FAQ wiki entry stale with regards to nohz=off option → Linux guest clock skew problems go away with nohz=off |
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comment:2 by , 16 years ago
Oups, guess I overlooked that.
I guess it could be mentioned in the section about Linux guests then.
comment:3 by , 16 years ago
Replying to robinsmidsrod:
The user faq states that setting nohz=off should not be necessary after virtualbox 1.6.
I'm running VirtualBox 3.0.4 on a Vista x64 host with a Ubuntu 8.04 server 32bit guest, and I had make clock skew problems consistently.
Setting nohz=off made it go away.
I have a SLES 10 SP2 amd64 guest under a Solaris 10 host where the guest clock ran about 1.5-2x the speed of the host clock.
- This happened with and without guest additions
- This happened on VB 3.0.4 and 3.0.6
- This happened with and without nohz=off
The solution to the problem was to run the guest with a non-SMP kernel so that I could disable the IO-APIC. Without IO-APIC the guest clock is accurate - with it, it drifts wildly.
comment:4 by , 14 years ago
| Resolution: | → fixed |
|---|---|
| Status: | new → closed |
Please reopen if still relevant with VBox 4.0.4.
Well, the wiki entry is related to Linux hosts while your problem is related to a Linux guest.