Wednesday, August 6, 2008

The problem of migrating virtual machines

The problem in cloud computing is the need to send virtual machines over a network connection. This basic requirement is illustrated in the following diagram.

Virtual machines need to have the ability to migrate from one physical machine to another. The problem is the huge latency involved, caused by the network bottleneck of transferring these machines over a network. The basic idea is illustrated in the following figure.

As you can see, the target physical machine has to wait until the entire machine has arrived before anything can be done with it. It would be nice if there were something the target machine could do with partial virtual machine data. In essence, a streaming virtual machine migration.