Ruby on rails网站，Heroku，自动重启

Question

I recently deployed my personal website built using RoR on heroku. today I tried to open my website and the site was down. If I wanna make sure the process restarts automatically is that a function of RoR or heroku? what are the best practices in this scenario?

Update : this is the heroku log to calrify the issue :

2013-06-10T08:24:12.852597+00:00 heroku[web.1]: Idling
2013-06-10T08:24:15.762803+00:00 heroku[web.1]: Stopping all processes with SIGTERM
2013-06-10T08:24:16.487918+00:00 app[web.1]: [2013-06-10 08:24:16] ERROR SignalException:   
SIGTERM 
2013-06-10T08:24:16.487918+00:00 app[web.1]:      
/usr/local/lib/ruby/1.9.1/webrick/server.rb:90:in `select'
2013-06-10T08:24:26.878674+00:00 heroku[web.1]: Error R12 (Exit timeout) -> At least one   
process failed to exit within 10 seconds of SIGTERM
2013-06-10T08:24:26.878857+00:00 heroku[web.1]: Stopping remaining processes with SIGKILL
2013-06-10T08:24:29.279913+00:00 heroku[web.1]: Process exited with status 137
2013-06-10T08:24:29.299601+00:00 heroku[web.1]: State changed from up to down

Answer 1

This is a function of Heroku. If you only have 1 dyno running, Heroku will set your site to idle after 1 hour of inactivity: https://devcenter.heroku.com/articles/dynos#dyno-idling

To avoid this, you need an external service like pingdom or NewRelic to ping your site at least once an hour and that will keep it from idling out.

Also, it's a good idea to make sure your site starts up fast so if it is idled or restarted, it will come back online quickly. But that is a topic for another question :)