openstack team mailing list archive

[Vishvananda Ishaya <vishvananda@xxxxxxxxx>]

On Oct 30, 2012, at 7:01 PM, Huang Zhiteng <winston.d@xxxxxxxxx> wrote:

> I'd suggest the same ratio too.  But besides memory overcommitment, I
> suspect this issue is also related to how KVM do memory allocation (it
> doesn't do actual allocation of the entire memory for guest when
> booting). I've seen compute node reported more memory than it should
> have (e.g. 4G node has two 1GB instances running but still report >3GB
> free memory) because libvirt driver calculates free memory simply
> based on /proc/meminfo, which doesn't reflect how many memory guests
> are intended to use.

Ah interesting, if this is true then this is a bug we should try to fix.
I was under the impression that it allocated all of the memory unless
you were using virtio_balloon, but I haven't verified.

Vish