How to shutdown all dynamic instances in Google App Engine without re-deploying the app?
Maybe have them all periodically probe the datastore (or memcache) for a kill value?
We are running multiple load tests every day against one of our GAE apps. We use the following pattern:

Start a load test and let it run for a few hours.
Look at graphs.
Optionally deploy a new version of our app with performance improvements.
Go back to 1.

Each load test creates a couple hundred front end instances. We would like to terminate those between individual load tests even when we are not deploying a new version of our app.
Is there a way to terminate all dynamic instances? Right now we either have to deploy a new version or terminate all instances by hand.