Making Parallels less of a CPU Hog when Idle.
Clever Dave likes Parallels for development, but doesn’t like that it is a cpu hog. An idle vm swallowed up 40-50% of cpu on his new Macbook.
He had the idea that reducing the speed of the kernel clock to 100MHz might make the idle vm less resource hungry, so we tested it out. Changing the clock speed did indeed reduce cpu usage from 40-50 to 10%. If you use debian in your Parallels VM and want the same kernel that has given him success, then you can download a Debian Kernel Package with this change in it from here. It’s the standard debian options, with the clock speed altered, and the version bumped to the latest on kernel.org.
[linux-image-2.6.22.3_slowclock.100_i386.deb] Just download and dpkg -i in your VM.
Posted: August 16th, 2007 under Sys Admin, Linux, parallels.
Comments: 3
3 Responses to “Making Parallels less of a CPU Hog when Idle.”
Write a comment
You must be logged in to post a comment.
Related articles
- Mac VNC Client for Linux KVM (March 30th, 2008)
- Internationalisation of DNS continues (February 8th, 2008)
- Text editors to be placed on endangered species list (January 21st, 2008)
- If VoIP kills phreaking, who are tomorrow’s engineers? (October 29th, 2007)
- Making the right ipv6 noises (October 25th, 2007)

August 16th, 2007 at 10:03 am
Thanks again, Andy. To shave off another couple of % I turned off some default devices I wasn’t using, like USB, and floppy and CD drives.
August 16th, 2007 at 11:16 pm
I remember seeing something somewhere (possibly LWN) about dynamic tick support going into the kernel recently.. perhaps that might be worth a look? I’ve not played with it myself yet though, mind.
August 17th, 2007 at 7:03 am
I shall have a look around. If this relies on the same time sources as the tickless kernel, then it is unlikely to work yet :
http://forum.parallels.com/thread14710.html