About half a year ago Vitaly posted a post about how simple it is today to use ruby patches bundled with rvm installation to dramatically reduce big rails app loading times and make your dev environment a much happier place.

Since then Ruby advanced with new patchlevels and there are new patches to use, so let’s go over this once again.

First, we start with upgrading the rvm to latest and hopefully greatest

rvm get head

Since Vitaly wrote his post it seems that the railsexpress patch superseded the falcon one. At least that what i got from browsing over the patches repository.

So, next step is to compile our Ruby version with railsexpress patchset applied

rvm install 1.9.3-p392-railsexpress --patch railsexpress

Ok, now for some trivial benchmarking to ensure we made things better and not the other way around. Now, note that the say in the interwebs goes that the bigger your application and amount of gems it has to load the more happy you will be. Also, the usual disclaimer about those performance things, YMMV.

I took a random application from my dev folder. It loads 147 gems. Let’s check out some numbers

✗ rvm use 1.9.3
Using /usr/local/rvm/gems/ruby-1.9.3-p392
✗ time rails runner "puts :OK"
OK
rails runner "puts :OK"  16.28s user 1.70s system 98% cpu 18.185 total

✗ rvm use 1.9.3-p392-railsexpress
Using /usr/local/rvm/gems/ruby-1.9.3-p392-railsexpress
✗ time rails runner "puts :OK"
OK
rails runner "puts :OK"  8.56s user 1.22s system 99% cpu 9.820 total

Just to make a comparison to the previous blog post, here are the numbers for the same application with ruby 1.9.3-p327 with falcon patches set:

✗ rvm use 1.9.3-p327-falcon
Using /usr/local/rvm/gems/ruby-1.9.3-p327-falcon
✗ time rails runner "puts :OK"
rails runner "puts :OK"  9.89s user 1.34s system 98% cpu 11.374 total

So, comparing to falcon patches it’s not that big of an improvement, but still, another 1.5 seconds win.

And yes, i know that both before and after times are slow. But still, i see a nice around 50% time save on any environment loading. And what i really like is that this improvement demanded the whole 7 minutes of my time.