~30% host CPU usage when guest Windows 7 x32 VM is at ~2%

[LeVeL5]

I read this post before: https://forum.parallels.com/threads/high-cpu-usage-in-host-when-guest-is-idle.327992/

~8.5% CPU for virtualization overhead plus 2% times 2 vCPUs equals ~12.5% host CPU usage, it should not be using the 30%~35% it's using now. My MBP 2011 is constantly running at 130 ºF and over. I'm using OS X Mavericks 10.9.5 and the latest Parallels 10.2.0.

Can someone shed some light on this? Thanks!

 

[Dhruba@Parallels]

Hi LeVeL5,
Please try creating an empty Virtual Machine and check the CPU usages. Refer to this article, http://kb.parallels.com/121578
Note: This article is also applicable for Parallels Desktop 10.

 

[LeVeL5]

Hi Dhruba,

No, it takes the same 30%~35% of CPU.

 

[PaulChristopher@Parallels]

Hi LeVeL5,
The reason why numbers are different is that Mac and Windows calculate CPU consumption in 2 different ways:

• In Windows: No matter how many CPUs you have, if you have (for example) 6 CPUs installed, the total consumption of all 6 CPU resources will equal 100%.
• In Mac: Multiply the number of CPUs you have by 100%. For example if you have 6 CPUs installed, the total consumption on Mac will equal 600%.

Some of the CPU power on the Mac side is also used for visualization purposes.
Please refer to this article to know about CPU consumption: http://kb.parallels.com/112764

Thanks,
Paul Chris