>> Want to run 2 4GB KVM VMs? The host needs to have more than 8GB available >> to it in order to dedicate RAM to the VMs as well as manage its own >> resources.
Not necessarily, and usually it's not so. It depends a lot on the workload on the guest systems and on the ability of the virtualization layer to handle a memory pressure scenario. > but i have given 3GB for my VM where the base system has 2GB of RAM. > i was just testing not for production. > > Base OS is Fedora 14 and Guest is RHEL6 This guest memory overcommitting is possible by: - using swap memory of the host system; - using memory overcommit on the host system; - using ksm on the host system. (possibly others, this is not intended to be an exhaustive list). You can check that there isn't any magic involved in this by running a small program on the guest that allocates big chunks of memory and fill them with data from /dev/urandom (to defeat the ksm merging mechanism) (of course without releasing the memory area after having filled it). _______________________________________________ rhelv6-list mailing list [email protected] https://www.redhat.com/mailman/listinfo/rhelv6-list
