Starting to see more real requests for this, maybe worth planning for implementation eventually once there's a strong use case.

Design proposal: http://go/single-use

Do we really want this now, only for Linux? E.g. installer use case is not even applicable to Linux (I think we use Debian packages, or something, there).

IMHO, it's better to make rest of the fleet (at least virtualized Windows and OSX) be as supported as GCE VMs, before adding more features there. Without doing so, we are just growing the pile of technical debt.

The proposal is hypervisor-agnostic, it's entirely Swarming-side. If we support single-use first then add other support in MP (e.g. Windows on GCE, Mac on vSphere) we would get single-use for free for those platforms. Alternately like you suggest we could support other OSes first and then the proposed single-use design could be implemented later.

Linux is the most represented OS on chromium-swarm with 1500/3500 bots being Linux, and 1300/3500 managed by MP. There are only about 700 Windows and 800 Mac. Far fewer if you only count VMs, because bare metal cannot easily be refreshed even if managed by MP.

I think this is a lower priority item as well. Swarming Linux GCE is already our most reliable platform, in part because of the 24-hour leases MP is already providing.

I'd much rather see projects that reduce labs team or trooper toil (e.g. MP for non-GCE or running Win10 on GCE).

The proposal is theoretically viable but in practice the startup delay for new VMs is significant. We likely can't do single-use VMs until we get the startup time way down.

keywords: delete, one use, reap

I'll dupe this issue into issue 906747, as I feel it is a slightly better design. It doesn't require keeping a counter of the number of tasks run on a bot, it just deletes it. As such, it's a slightly different use case than what is described at http://go/single-use but I think it better defines what is needed: the caller can ask for the bot's VM to be reaped.