[CentOS] Re: Not seeing all memory in CentOS 5.1 x86_64

[Ruslan Sivak]

Tim Verhoeven wrote:
> On Wed, Jun 11, 2008 at 4:46 PM, Ruslan Sivak <russ at vshift.com> wrote:
>   
>> While it seems to make sense (and both xentop and virsh nodeinfo) show the
>> right amount of memory, even when I shut down one of the VM's, free and top
>> still think I only have 6GB of ram.
>>     
>
> That is normal, the memory that was used by VM's is not automatically
> returned to the dom0 and therefore won't show when running free and
> top.
>
> Regards,
> Tim
>
>   
I guess it has something to do with the ballooning driver for Dom0.  It 
looks like I just tried to allocation too much memory to DomU and the 
box went down hard.  I think there's a setting in xen to the min amount 
of memory to go down to, but I'm not sure why Dom0 is using 600mb of 
RAM.  Is there a mini installation of CentOS that I can do that would 
use less RAM?  I've already unchecked all the boxes when installing 
CentOS. I would like Dom0 to be as small as possible, both due to RAM 
usage and from a security perspective. 

Russ