Virtualization and over-subscription: breaking the 100% utilization barrier

I can still remember the first time I put together a vmware virtualcenter server with a few servers running the hypervisor. It was the first time I encountered software that left me speechless since it felt like it was built with magic, at the time since I simply couldnt comprehend how this could be done.<p>I ended up quitting the company I built it at because they didnt see the point of virtualization and werent going to implement it.

Also of possible interest - things we've done with the current (1.1) version of our platform:<p>Howto: Build and scale a Cassandra cluster in five minutes - <a href="http://blog.gridcentriclabs.com/2010/08/howto-build-and-scale-cassandra-cluster.html" rel="nofollow">http://blog.gridcentriclabs.com/2010/08/howto-build-and-scal...</a><p>Howto: Build a Hadoop cluster in five minutes - <a href="http://blog.gridcentriclabs.com/2010/07/howto-build-hadoop-cluster-in-five.html" rel="nofollow">http://blog.gridcentriclabs.com/2010/07/howto-build-hadoop-c...</a><p>Howto: Build a ten node memcached cluster in five minutes - <a href="http://blog.gridcentriclabs.com/2010/07/how-to-build-10-core-memcached-cluster.html" rel="nofollow">http://blog.gridcentriclabs.com/2010/07/how-to-build-10-core...</a><p>You may notice an interesting trend :)<p>[edit: formatting]

Actually OpenVZ already has a lot of the things mentioned, although only for Linux VMs running on top of an OpenVZ-ified Linux kernel.<p>Paging, ballooning, content-based sharing, CPU and RAM overcommit, all are there, provided you only use Linux VMs.