Rbenv Ruby Upgrade

rbenv_ruby-2.2.2.md

Install Ruby 2.2.2

cd ~/.rbenv/plugins/ruby-build
git pull
rbenv install 2.2.2

https://github.com/sstephenson/rbenv

Set the current shell to use it, and prepare for Rails - This won't affect current install

rbenv shell 2.2.2
gem install bundler
bundle install
rbenv rehash

When the above works correctly, it should be safe to deploy and set the shell permanently

rbenv global 2.2.2
rbenv which rake # Make sure we're defaulting to the correct ruby

We also need to make rbenv aware of gem's binaries, or the console and CLI won't work

mkdir -p ~/.rbenv/plugins
cd ~/.rbenv/plugins
git clone https://github.com/ianheggie/rbenv-binstubs.git 
cd YOUR_APP
bundle install --binstubs .bundle/bin
rbenv rehash

https://github.com/ianheggie/rbenv-binstubs https://github.com/sstephenson/rbenv/wiki/Understanding-binstubs (This approach didn't work for me)

Alternativelty, you can just install the same gems to the local env (which seems wrong)

bundle install

NOTE: This means when you upgrade a gem, it has to be upgraded on the server as well

You've also got to update the unicorn file in /etc/init.d to use ruby version 2.2.2

And now that we're updated, a few resources on optimizing, specifically GC

http://www.collectiveidea.com/blog/archives/2015/02/19/optimizing-rails-for-memory-usage-part-2-tuning-the-gc/ http://tmm1.net/ruby21-rgengc/ http://engineering.freeagent.com/2014/05/23/upgrading-to-ruby-2.1/