Rolls a Looks or site generator release out to every published site. The run walks users a batch at a time, so Redis never holds more than one batch. Every page it publishes is stamped with the build that rendered it, so an interrupted run can be finished later without redoing what is done.
Every enabled user with a site, or only those who signed up in a date range (UTC, both days included). Set a range to see who it would touch before starting.
No range set: a run walks every enabled user with a site.
Throughput scales with the Sidekiq worker dynos on milkshake-api-prod. Each thread keeps one site generator process alive for the run; scale workers up to go faster, and back down when the run is finished.