Using NAT increases CPU utilization to 60%

bandit · Post by **bandit** » 29. Aug 2008, 01:03

I am able to run Skype(ver. 3.5.??). Even running skype (alone) also leads to high cpu utilization. I have tried enable/disabling windows firewall as well as ubuntu firewall. But it doesnt have any effect.

bsmith1051 · Post by **bsmith1051** » 5. Sep 2008, 17:21

I have a Win2000 guest on my Ubuntu 8.04 host. I always have appr 30% cpu on the host (and on BOTH cores!) even when the guest shows "0%" in it's Task Manager. And this is with no network activity in the guest. I've had this problem forever, near as I can tell. My host is fast enough that I didn't notice it, I just happened to check my CPU usage one day. That was way back in the VirtualBox 1.4 days, and the problem has persisted through every version up to and including the new 2.0.

EDIT: I just checked and I'm running the HAL ACPI. Is that the problem? If I understand correctly, the only way to change this is to recreate the image?

bandit · Post by **bandit** » 5. Sep 2008, 17:25

bsmith1051 wrote:I have a Win2000 guest on my Ubuntu 8.04 host. I always have appr 30% cpu on the host (and on BOTH cores!) even when the guest shows "0%" in it's Task Manager. And this is with no network activity in the guest. I've had this problem forever, near as I can tell. My host is fast enough that I didn't notice it, I just happened to check my CPU usage one day. That was way back in the VirtualBox 1.4 days, and the problem has persisted through every version up to and including the new 2.0.

Do you see higher cpu utilization while running google talk/yim or the problem exist even when nothing is running.

bsmith1051 · Post by **bsmith1051** » 5. Sep 2008, 18:36

even with nothing running.

And, I just tried updating my HAL from "Advanced Computer blah blah (ACPI)" to "ACPI uniprocessor" ... and now it won't boot. Oops!

Post by **TerryE** » 5. Sep 2008, 19:46

Is this a VDI or Raw partition? If the former, I assume that you made a snapshot before applying these changes.

Post by **Sasquatch** » 5. Sep 2008, 19:47

For your reference, I tested this with Windows Live Messenger and I did not have a higher CPU load on both ends (Guest and Host) while talking to someone. There must be something wrong with one of your installed systems (Host or Guest).

noiv · Post by **noiv** » 7. Sep 2008, 01:25

I can confirm CPU load on Ubuntu Hardy with W2K guest while
no interaction with the system and no background tasks active.

Even with disabled network device (host + guest), shared folders and USB devices.
The load is constantly 38% and oscillates from one core to the other
without any (recognisable) system. The cpu fan is noisy.

What else can be checked to nail down this well - strange - behaviour? Against what resource is VB polling?

Post by **Sasquatch** » 7. Sep 2008, 20:11

What process on the Guest system is taking all that CPU? And don't say it's the "System Idle Process" because that is natural

.

adf · Post by **adf** » 9. Sep 2008, 02:04

My host is mini mac core2 with Ubuntu Hardy host OS, Virtualbox 1.6.6 and several xp SP3 guests on NAT.

If I run only one vm I get more than 60% cpu load ( one core ) - when I start another vm, load drops to approx. 8% on each core.

adf · Post by **adf** » 9. Sep 2008, 02:10

... and yes: The first ( problematic ) virtual machine is running VTtrader demo, so network is being utilized non-stop. CPU usage in vm's task manager is about 30%.

Second vm is idle fresh XP install.

Both vms have windows updates disabled.

I understand that CPU is not supposed to stay idle, but I would like to know why CPU usage drops when another machine is started.

virtualbox.org

Using NAT increases CPU utilization to 60%

same problem here