Re: [tlug] Assigning Multiple CPU Cores to a VirtualBox

[Christian Horn <chorn@example.com>]

On Sun, Mar 01, 2015 at 10:38:20AM +0900, Travis Cardwell wrote:
> On 2015年03月01日 10:10, CL wrote:
> 
> The top answer on the following page explains virtual cores well:
> http://superuser.com/questions/297697/are-there-any-real-advantages-to-assigning-more-cores-to-virtualbox
> 
> Assigning virtual cores does *not* give exclusive control of physical
> cores to the guest.  RAM, on the other hand, should be guaranteed.

I would recommend KVM, then the RAM of the guest is just like a
normal process, can also be swapped etc.


> If you are serious about improving performance, do not use VirtualBox.
> From my experience, VirtualBox is considerably slower than the
> alternatives, such as VMware and Xen.

+1
I see VirtualBox used when people need a free (as in beer) 
solution which works on all Linux/Mac/Win, and even then VMware 
player might also apply.

For practical testing that the cores are really available to 
processes on the host:

- while the 4 core VM is running but is idling
- you could open 8 terminals on the host system
- run "md5sum /dev/urandom" in each
- run "top" in a further terminal
- observe that each of the 8 md5sum processes gets to run on
  an own core

The "dedicated cores for the guest" configs are with KVM also 
possible, but most make no sense for most usecases.

Chris