Timekeeping in stable/9

[Joe Holden]

Ronald Klop wrote:
> On Sat, 21 Jan 2012 14:11:51 +0100, Martin Sugioarto 
> <martin at sugioarto.com> wrote:
> 
>> Am Sat, 21 Jan 2012 13:20:51 +0100
>> schrieb "Ronald Klop" <ronald-freebsd8 at klop.yi.org>:
>>
>>> Hi,
>>>
>>> As I understand it.
>>> Host: FreeBSD 9
>>> Guest: WinXP
>>>
>>> Which one has troubles with its clock? The host or the guest or both?
>>
>> Hi,
>>
>> only inside VirtualBox, I think it's only an application problem and
>> my emails would be probably better addressed to ports at . ONLY the guest
>> is affected when host is loaded.
>>
>> I noticed additionally:
>>
>> You get better results with a desync'ed clock in the guest system, when
>> you start "openssl speed -multi 20" or similar. Within a few seconds the
>> clock gets a 20 seconds difference.
>>
>>> How many CPU's did you assign to the guest?
>>> Did you install virtualbox guest additions to the guest?
>>
>> Here a few details (guest additions are installed):
>>
>> Memory size:     1600MB
>> Page Fusion:     off
>> VRAM size:       256MB
>> HPET:            on/off (tried both settings)
>> Chipset:         piix3
>> Firmware:        BIOS
>> Number of CPUs:  1
>> Synthetic Cpu:   off
>> CPUID overrides: None
>> [...]
>> ACPI:            on
>> IOAPIC:          off
>> PAE:             on
>> Time offset:     0 ms
>> RTC:             local time
>> Hardw. virt.ext: on
>> Hardw. virt.ext exclusive: on
>> Nested Paging:   on
>> Large Pages:     on
>> VT-x VPID:       on
>> [...]
>> 3D Acceleration: off
>> 2D Video Acceleration: on
>>
>>> Do you run NTP on the guest XP also? If yes, turn it off.
>>
>> Windows XP default installation (synch'ed to time.windows.com).
>> Switching this off, does not have any influence. I think MS-Windows
>> does not do continuous synchronization, only at system start, I guess.
>>
>>> VBox guest additions can sync the guest clock with the host.
>>
>> I'll try to deinstall them. But I somehow like my shared folder.
>>
>>> BTW: My experience with VBox is that it is nice for hobby stuff, but
>>> not for heavy load server stuff. VMWare does a better job there.
>>
>> Yes. I know. Still VirtualBox ist nice and cheap solution.
>>
>> -- 
>> Martin
> 
> BTW: I used VBox on Linux at work. Same problems. Different problems 
> come and go with different versions of Linux in combination with 
> different versions of VirtualBox. Using VmWare ESXI solved it. If you 
> search a lot on the vmware website you will find a free version.
> 
> Ronald.
In the extreme case I have here, the host isn't taxed at all, cpu, disk 
i/o and such are almost idle but the time is skewed dramatically regardless.

For reference the settings I have are:

4 VCPUS (4 physical cores)
1GB ram
ICH9, SAS controller

If I toggle the sysctl in my previous post the problem goes way, and 
doesn't return even if the sysctl is changed back... until a reboot of 
course.  None of the pre-9 guests (there are quite a few spread across a 
couple of identical machines) exhibit the behaviour, nor does this 
particular one when reverted to a pre-upgrade snapshot, so in this case 
it is certainly not the hardware but whatever is used to keep track of 
the "ticks" (terminology probably incorrect)

Thanks,
J