

Ask HN: What do I need to know about Heroku to launch my app? - guynamedloren

I have been developing my first rails application using free server space from Heroku.  Now that I am pondering going live (a small private beta), I'm assuming that I'll have to move beyond the free space I've been developing with.  The problem is I know absolutely nothing about any of this - dynos, workers, etc.  I've looked over the Heroku website and docs a few times, but it looks like it requires a basic level of sys admin knowledge - something I certainly do not have.<p>How do I know how many dynos or workers to add?  What if I add too many and I'm wasting money?  Or do they scale up as needed?  Do I need a dedicated database?  I read something about free Heroku apps shutting down if idle for 24 hrs, causing a short delay the next time the app is launched.  How do I prevent this from happening?  Please educate me on Heroku, HN!<p>Thanks!
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jjoe
Benchmark! That's how. Order the least amount of resources and then benchmark
your app to see how well it's performing. If your goal is handle 100 req/s,
then benchmark with that goal in mind. Your benchmark unit tests need to touch
the whole stack (Ruby & SQL).

As for the 24-hrs idle time, run a periodic script that keeps it alive (by
simulating a valid app action).

I'm not a Heroku user.

Regards

Joe

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nolite
Filesystem is read only, so nothing that writes to disk

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guynamedloren
Care to elaborate? I'm not sure what you're referring to here..

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nolite
sorry.. perhaps this is a better explanation

<http://docs.heroku.com/constraints>

Another example, if you're using Sass for CSS, I don't think that works
seamlessly either due to this read-only filesystem restriction

As for the delay to restart your app.. its really nothing to worry about.. its
probably on the order of a few more hundreds of milliseconds, but if its shut
down due to low traffic, you probably don't need that kind of responsivity
anyway. If its getting alot of traffic, then this sleep period shouldn't
happen.

