[VBox] Why VirtualBox process is so large?

[Yuri]

On 12/13/2013 02:02, Yuri wrote:
> I have the VM that is allocated 512MB of base memory for the guest, 
> but its total memory size on host is 1263MB. This seems excessive.
> What is the normal memory overhead for the VM? Is there a way to 
> reduce it?
> Documentation doesn't elaborate on this.

512MB machine looks in ps(1) like this (linux guest):
5717 yuri         21  20    0  1263M   444M select  0   9:06 88.48% 
VirtualBox
And 1024MB machine looks like this (FreeBSD guest):
13565 yuri           18  20    0  1720M  1135M uwait   5  71:13 4.05% 
VirtualBox

Process sizes shouldn't be that high in both cases. My guess is that 
VBox takes freedom to allocate an additional disk cache maybe? Then this 
should be configurable. What other memory could this be? Leak?

As a comparison, VMWare lists the sample overhead memories: 
http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.resmgmt.doc_50%2FGUID-B42C72C1-F8D5-40DC-93D1-FB31849B1114.html
For 1GB machine with 1CPU it would be ~26MB. We need to understand why 
VBox goes so much higher.

Yuri