Asset compilation slow for EmberJS

Question

We're in the process of transitioning our front-end to EmberJS and plan to use the Ember CLI which should solve the problem we are currently having. Until that time we have multiple Ember JS applications in our Rails app. Running rake assets:precompile locally executes in less than a minute however asset compilation when deploying to Heroku is extremely slow (> 15 minutes) despite the use of PX dynos for deployment.

Here's our build log: https://gist.github.com/dior001/1d59deaff61ee243df7d

Note the compile times of approximately 4 minutes per EmberJS app.

• application_ember_orders => 2015-03-24T21:54
• application_ember_search => 2015-03-24T21:58
• application_ember_search_chrome => 2015-03-24T22:02

Has anyone experienced this problem with EmberJS and the Rails asset pipeline? If so do you have any suggestions about why compilation is so sluggish?

Answer 1

I've not run into this particular problem but Heroku can be picky about precompiled assets, so running rake assets:clean or even rake assets:clobber before deployment has worked for me in the past. The first one only cleans out old assets, but the second is a bit more forceful.