Host CPU usage spike with guest (windows XP) launches Yahoo Messenger

[boston_sb]

Problem Description
The host CPU usage spikes when Yahoo messenger is launched in the Guest. The spike goes away when Yahoo Messenger is terminated. I'm marking this as 'Major' because one of the reasons that I use Virtualbox is it's better processor usage than VMware. This problem makes Virtualbox worse, however.

I've attached screen shots from my gnome-system-monitor when the guest is running and not running yahoo, and also screen shots from the guest when itself is running and not running yahoo. The spike in the host is much more dramatic than the normal rise in CPU usage in the guest.

In top, the usage was ~70% when guest running yahoo, and ~12% when not running. gnome-system-monitor reports this a bit differently in the screen shots, I think because it's accounting for my dual-core system.

I've also included PIT log lines at the end of this post which coincide with running and terminating Yahoo messenger in the guest.

To duplicate
Launch Yahoo Messenger in Windows XP.
Expected: CPU levels rise appropriately in the guest and the host.
Observed: CPU levels in the host rise much more than they should. The guest rises slightly as expected - and your fan starts blowing :)

Host System:
Fedora 8 Linux
Linux localhost.localdomain 2.6.24.4-64.fc8 #1 SMP i686 GNU/Linux
VirtualBox 1.6.0

Guest System
Windows XP Professional
Yahoo Messenger 8.1.0.421

Log Lines -- The PIT lines with the high Hz correspond to running yahoo, the low ones correspond with not running it.
00:06:36.678 Display::handleDisplayResize(): uScreenId = 0, pvVRAM=04271000 w=1296 h=920 bpp=32 cbLine=0x1440
00:06:36.679 VBVA: Disabled.
00:06:36.679 VBVA: Enabled.
00:16:32.482 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)
00:21:14.144 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)
00:21:16.252 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)
00:21:17.099 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)
00:21:18.226 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)
00:21:36.507 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)
00:21:49.751 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)
00:29:34.925 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)
00:30:15.303 PIT: mode=2 count=0x2ead (11949) - 99.85 Hz (ch=0)
00:31:49.429 PIT: mode=2 count=0x4ad (1197) - 996.81 Hz (ch=0)

[boston_sb]

Memory readings from guest and host

[Frank Mehnert]

Please reopen if still relevant with VBox 4.1.6.