CPU usage 15% on virutal machines.

[rgesswein]

I've noticed that my CPU utilization jumps to 15-20% and stays there when I have XYplorer running in a virtual machine. I've noticed this with both Virtual PC 2007 and Virtual Box latest version.

Within the virtual machine XYplorer doesn't show up with the usage, it's on the host machine where this is showing up (as virtual machine activity), but only when XYplorer is running. Also, Windows explorer does not show this behavior, so it's something unique to XYplorer that Windows explorer is not doing.

Any idea what might be causing this? Can anyone else confirm this?

[John Bee]

I've noticed that my CPU utilization jumps to 15-20% and stays there when I have XYplorer running in a virtual machine.

Yes, for me too. Both in Linux and Win and VirtualBox. Now at version 1.5

[admin]

Any idea what might be causing this? Can anyone else confirm this?

Not really. Try turning off Auto-Refresh (but I don't really think it can cause that much usage).

[rgesswein]

No good. I tried turning off most every option and there was no change to CPU utilization.

[tgrand]

I have the same problem. After some investigation, I believe I've found the cause. It's described in this ticket:
http://www.virtualbox.org/ticket/3613

Windows programs that request high-resolution timing cause the number of RTC interrupts to increase to around 1000Hz. This incurs additional host CPU usage when it's happening in a VM. The interrupt rate change is clearly visible in the VirtualBox log file. When I start XYplorer, I see the following:

Code: Select all

00:01:00.473 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)

When I close XYplorer, I see the following:

Code: Select all

00:01:30.504 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)

PIT is the programmable interval timer, the system timer that generates timing interrupts. I theorized that while any apps that have called beginTimePeriod(1) are running, the virtual PIT is set to ~1000Hz. When those apps are closed, it's restored to a lower rate (~100Hz in my current VM state). I tested my theory by creating a Win32 console app that only calls beginTimePeriod(1) once and then calls Sleep() to sleep indefinitely. The behavior was exactly the same as with XYplorer: increased interrupt frequency and CPU usage on the host.

Is XYplorer calling beginTimePeriod(1)? If so, could you please stop doing that or give the user an option to stop doing that? I'm not sure if the problem will ever be solved on the VirtualBox side, but it might be very easy to solve on the XYplorer side. I would appreciate a solution as I currently need to keep opening and closing XYplorer in my VM to avoid excessive CPU usage on the host (which is especially bad on OS X).

[admin]

Wow, very interesting!

Is XYplorer calling beginTimePeriod(1)? If so, could you please stop doing that or give the user an option to stop doing that? I'm not sure if the problem will ever be solved on the VirtualBox side, but it might be very easy to solve on the XYplorer side. I would appreciate a solution as I currently need to keep opening and closing XYplorer in my VM to avoid excessive CPU usage on the host (which is especially bad on OS X).

Indeed, I'm calling it! I will stop it and see what happens.

[John Bee]

Indeed, I'm calling it! I will stop it and see what happens.

! Might have fixed an issue where CPU utilization jumps to 15-20%
and stays there when XYplorer is running in a virtual machine.

That did the trick, Don. Thank you very much. I can now use XY again in VBox.

[admin]

Indeed, I'm calling it! I will stop it and see what happens.

! Might have fixed an issue where CPU utilization jumps to 15-20%
and stays there when XYplorer is running in a virtual machine.

That did the trick, Don. Thank you very much. I can now use XY again in VBox.

Great!! But thanks should go to tgrand!

[John Bee]

Great!! But thanks should go to tgrand!

Oh yes, tgrand, thank you. If it wasn't for you figuring this out, I still wouldn't be using XY

As I am no longer a windows user, the only place where XY resides is in a VM. And even in a
VM, it still does things that I cannot do in a linux filemanager. (I let XY see my linux file systems via
a share in VBox, so I can manipulate/massage linux files/folders with XY from inside the VM. )

Again, thanks to you both!

[tgrand]

Glad I could help!

Thanks for getting this fix out so quick. I just tried the latest beta version and the problem is definitely solved. Excellent!