Capistrano tasks for starting unicorn

Capistrano tasks for starting unicorn.rb

set :rails_env, :production
set :unicorn_binary, "/usr/bin/unicorn"
set :unicorn_config, "#{current_path}/config/unicorn.rb"
set :unicorn_pid, "#{current_path}/tmp/pids/unicorn.pid"

namespace :deploy do
  task :start, :roles => :app, :except => { :no_release => true } do 
    run "cd #{current_path} && #{try_sudo} #{unicorn_binary} -c #{unicorn_config} -E #{rails_env} -D"
  end
  task :stop, :roles => :app, :except => { :no_release => true } do 
    run "#{try_sudo} kill `cat #{unicorn_pid}`"
  end
  task :graceful_stop, :roles => :app, :except => { :no_release => true } do
    run "#{try_sudo} kill -s QUIT `cat #{unicorn_pid}`"
  end
  task :reload, :roles => :app, :except => { :no_release => true } do
    run "#{try_sudo} kill -s USR2 `cat #{unicorn_pid}`"
  end
  task :restart, :roles => :app, :except => { :no_release => true } do
    stop
    start
  end
end

why not change restart to just reload instead of stop,start?

Reload task it's for reread config file, some sort of soft restart. Restart task is for hard restart, added just in case.

just made a test here and using reload, it reloaded the app code too. I think it's better(and faster) then the stop/restart process http://unicorn.bogomips.org/SIGNALS.html

If restart as usual, when you deploy for example, then you are right. I use reload task in the most of cases. But sometimes need to use hard reset, in case of server glitches.

The letter flag itself is optional: both kill USR2 and kill -s USR2 do the same thing.

Minor tip, might help speed up a bit. Instead of using ruby backticks for the PID, do it the UNIX way.

run "kill -s USR2 $(< #{unicorn_pid})"

Thanks