Puma + nginx for rails

default

# /etc/nginx/sites-enabled/default

upstream app {
    # Path to Puma SOCK file, as defined previously
    server unix:///var/www/html/shared/sockets/puma.sock fail_timeout=0;
}

server {
    listen 80 default_server;
    listen [::]:80 default_server ipv6only=on;
    
    server_name localhost;

    root /var/www/html/current/public;

    try_files $uri/index.html $uri @app;

    location @app {
        proxy_pass http://app;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Request-Start "t=${msec}";
        proxy_set_header Host $http_host;
        proxy_redirect off;
    }

    error_page 500 502 503 504 /500.html;
    client_max_body_size 4G;
    keepalive_timeout 10;

    location /admin/sidekiq {
        auth_basic "Restricted";
        auth_basic_user_file /etc/nginx/.htpasswd;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;
        proxy_pass http://app;
    }
}

puma.conf

# /etc/init/puma.conf
description "Puma"

start on runlevel [2]
stop on runlevel [016]

# change to match your deployment user
setuid root
setgid root

respawn

script
exec /bin/bash <<'EOT'
  source /usr/local/rvm/bin/rvm
  cd /var/www/html/current
  RAILS_ENV=production bundle exec puma -C /var/www/html/current/config/puma.rb
EOT
end script

puma.rb

# config/puma.rb

cpu_count = `cat /proc/cpuinfo | grep processor | wc -l`.to_i
workers cpu_count

threads 20, 20

app_dir = "/var/www/html/current"

rails_env = "production"
environment rails_env

bind "unix:///var/www/html/shared/sockets/puma.sock"

pidfile "/var/www/html/shared/pids/puma.pid"
state_path "/var/www/html/shared/pids/puma.state"
activate_control_app

stdout_redirect '/var/www/html/shared/log/puma.log', '/var/www/html/shared/log/puma.log', true

on_worker_boot do

end

before_fork do
  require "puma_worker_killer"

  free_memory_mb = `cat /proc/meminfo | grep MemAvailable`.gsub(/.*:/, "").to_i / 1024

  PumaWorkerKiller.config do |config|
    config.ram           = free_memory_mb
    config.frequency     = 60
    config.percent_usage = 0.98
    config.rolling_restart_frequency = 3600
    config.reaper_status_logs = true
  end

  PumaWorkerKiller.start
end