Back in May, Google announced that it would be offering its Compute Engine VMs in a new flavor. Called preemptible VMs (presumably as opposed to contemptible VMs which would be far less desirable), these compute instances are priced at rock bottom — at a 70% discount to regular instances.
There is, however, a catch. Preemptible VMs can be shut down at any time and are limited to a 24-hour runtime. To add to the uncertainty, users get only 30 seconds’ notice of a VM shutdown. Ouch.
Of course there is a method to the madness and certain workloads lend themselves to this level of transience in terms of computing. A situation where a huge compute job needs to be done, but isn’t time critical, and has an operational management layer sitting above it, for example. Another mooted suggestion is to use these VMs to enhance performance while running the main part of an application on conventional VMs to maintain uptime. Load or security testing look like another useful use case for these most temporal of instances.