chore(puma): Tweak puma configuration (#2037)

- Tweak puma configuration to improve performances

config/puma.rb

@@ -7,13 +7,14 @@
 # and maximum; this matches the default thread size of Active Record.
 #
 max_threads_count = ENV.fetch('RAILS_MAX_THREADS', 5)
-min_threads_count = ENV.fetch('RAILS_MIN_THREADS') { max_threads_count }
+min_threads_count = ENV.fetch('RAILS_MIN_THREADS', 0)
 threads min_threads_count, max_threads_count
 
 # Specifies the `worker_timeout` threshold that Puma will use to wait before
 # terminating a worker in development environments.
 #
 worker_timeout 3600 if ENV.fetch('RAILS_ENV', 'development') == 'development'
+worker_timeout 12 if ENV.fetch('RAILS_ENV', 'production') == 'production'
 
 # Specifies the `port` that Puma will listen on to receive requests; default is 3000.
 #
@@ -39,7 +40,7 @@
 # before forking the application. This takes advantage of Copy On Write
 # process behavior so workers use less memory.
 #
-# preload_app!
+preload_app! if ENV['WEB_CONCURRENCY'].present?
 
 # Allow puma to be restarted by `bin/rails restart` command.
 plugin :tmp_restart