Asset pre-compilation unbearably slow: Have we outgrown asset pipeline?

Our application is a very large (read: “enterprise”) Single Page
Application.

Even though our app is 99% client side with a Java RESTful API, we built
the web application on top of rails because the Asset Pipeline seemed
like
a a great fit for us. And until recently, it was.

Our application has several hundred CoffeeScript and SASS files in it
(as
we’ve broken our code down in to many smaller pieces for reusability).

We deploy to Heroku, who automatically compiles assets for us. It used
to
be pretty fast. Then it was a minute. Then 2. Then 5. Now, we have
apparently hit the upper limit that Heroku is willing to wait for assets
to
compile (15 mins).

Pre-compiling the assets on a developers machine is possible but its
error
prone and doesnt solve the problem of our compilation process taking
forever.

I notice that even some of our smaller CoffeeScript files (~50 lines)
take
250ms to compile. This quickly adds up with the amount of files we have.

On my i7 MBA, assets:precompile:primary takes around 5 minutes and
assets:precompile over 10 minutes. I think (but not sure) the biggest
problem is that it appears that a new nodejs process is started for
every
CoffeeScript file and each start takes a bit of time before the file is
even processed.

We are on the latest Rails 3.2.x. Is there a better way? Is there any
tuning I can do for improving the speed of compilation?

On Fri, Jun 28, 2013 at 12:11 AM, Bryan Migliorisi
[email protected]wrote:

We deploy to Heroku, who automatically compiles assets for us. It used to

On my i7 MBA, assets:precompile:primary takes around 5 minutes and
assets:precompile over 10 minutes. I think (but not sure) the biggest
problem is that it appears that a new nodejs process is started for every
CoffeeScript file and each start takes a bit of time before the file is
even processed.

We are on the latest Rails 3.2.x. Is there a better way? Is there any
tuning I can do for improving the speed of compilation?

try looking at https://github.com/ndbroadbent/turbo-sprockets-rails3

On Thursday, 27 June 2013 09:11:44 UTC-7, Bryan Migliorisi wrote:

250ms to compile. This quickly adds up with the amount of files we have.

On my i7 MBA, assets:precompile:primary takes around 5 minutes and
assets:precompile over 10 minutes. I think (but not sure) the biggest
problem is that it appears that a new nodejs process is started for every
CoffeeScript file and each start takes a bit of time before the file is
even processed.

We are on the latest Rails 3.2.x. Is there a better way? Is there any
tuning I can do for improving the speed of compilation?

This might help, if you’re deploying to Heroku mostly with assets
unchanged:

http://www.thirdprestige.com/posts/how-7-lines-of-ruby-will-speed-up-your-heroku-deploys-10x

Thanks for the suggestions. I actually set up the
turbo-sprockets-rails3
gem and buildpack and the difference is night and day. The first build
after switching took only 4 minutes which is way better than the 15+ it
was
taking before. Consequent builds are taking 30 seconds. Amazing.

Im guessing it uses a similar approach under the hood to what this blog
post is proposing, but I have not had the time to dig deeper into the
code
yet.

Thanks for the help guys
–Bryan