2011/4/14 Sandy Walsh <[email protected]>: > Let's not confuse instance metadata with Compute Node Capabilities. > > When scheduling, the instance has not been created yet. We have to make > decisions on where the instance will ultimately reside on a number of factors: > > 1. the capabilities of the host hypervisor (the Compute node) > 2. the current load the host is under > 3. the distribution policies of the customer (ie. "don't put all my instances > on the same host/zone, etc")
I still question the usefulness of nr. 2. A host that is almost completely idle right now might be under tremendous pressure a minute from now and vice versa. Even if we had useful statistics (and trend analysis) of the existing VM's on the host, we have no data at all on the requirements of the instance we're about to launch. It seems to me that the current load only affects the time it will take to spin up the new instance, and as such says nothing about its long term (or even medium or short term!) suitability as the new instance's home. -- Soren Hansen Ubuntu Developer http://www.ubuntu.com/ OpenStack Developer http://www.openstack.org/ _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : [email protected] Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
