Zero downtime on Heroku

Question

Is it possible to do something like the Github zero downtime deploy on Heroku using Unicorn on the Cedar stack?

I\'m not entirely sure how the restart works on Heroku

Answer 1

No - this is currently not possible using Unicorn on Heroku cedar. I've been bugging Heroku about this for weeks.

Here was Heroku Support's reply to my email on March 8, 2012:

Hi, you could enable maintenance mode when doing a deploy, at least your users would see a maintenance page instead of an error, and also request queue wouldn't build up.

We're definitely aware this is a pain and we're working to offer rolling / zero-downtime deploys in the future. We have no ETA to announce, though.