KVM Node running out of RAM

[Tony Fica]

We have several KVM nodes running Cloudstack 4.4.2.  Sometimes an 
instance with X amount of RAM provisioned will be started on a host that 
has X+a small amount of RAM free. The kernel OOM killer will eventually 
kill off the instance.  Has anyone else seen this behavior, is there a 
way to reserve RAM for use by the host instead of by Cloudstack? Looking 
at the numbers in the database and the logs, Cloudstack is trying to use 
100% of the RAM on the host.

Any thoughts would be appreciated.
Thanks,

Tony Fica