supervisord ＋ unicornでhot restart (deploy) する ref: http://qiita.com/kazuph/items/55a5f74b9dca2d17bd65

file0.txt

pip install git+https://github.com/kazuph/unicornherder.git

file1.ini

[web]
command=bash -lc 'bundle exec unicornherder -u unicorn_rails -p tmp/pids/unicorn.pid -- -c config/unicorn.rb -E production'
numprocs=1
autostart=true
autorestart=true
stopsignal=QUIT
startsecs=1
user=yourname
redirect_stderr=true
stdout_logfile=/var/log/appname/app/app.log
stdout_logfile_maxbytes=0
stdout_logfile_backups=0
stderr_logfile=/var/log/appname/app/app.log
stderr_logfile_maxbytes=0
stderr_logfile_backups=0
environment=HOME="/home/app",USER="app"
directory=/home/yourname/appname

file2.txt

$ cd /path/yourname/appname
$ kill -USR2 `cat tmp/pids/unicorn.pid`

file4.txt

Use of --pid/-P is strongly discouraged
Use the 'pid' directive in the Unicorn config file instead

file5.txt

  opts.on("-P PATH", "DEPRECATED") do |v|
    warn %q{Use of -P is ambiguous and discouraged}
    warn %q{Use --path or RAILS_RELATIVE_URL_ROOT instead}
    ENV['RAILS_RELATIVE_URL_ROOT'] = v
  end

file6.diff

-    'unicorn': 'unicorn -D -P "{pidfile}" {args}',
-    'unicorn_rails': 'unicorn_rails -D -P "{pidfile}" {args}',
-    'unicorn_bin': '{unicorn_bin} -D -P "{pidfile}" {args}',
+    'unicorn': 'unicorn -D {args}',
+    'unicorn_rails': 'unicorn_rails -D {args}',
+    'unicorn_bin': '{unicorn_bin} -D {args}',

herder.py

COMMANDS = {
    'unicorn': 'unicorn -D -P "{pidfile}" {args}',
    'unicorn_rails': 'unicorn_rails -D -P "{pidfile}" {args}',
    'unicorn_bin': '{unicorn_bin} -D -P "{pidfile}" {args}',
    'gunicorn': 'gunicorn -D -p "{pidfile}" {args}',
    'gunicorn_django': 'gunicorn_django -D -p "{pidfile}" {args}',
    'gunicorn_bin': '{gunicorn_bin} -D -p "{pidfile}" {args}'
}