add RAILS_MIN_THREADS, RAILS_MAX_THREADS, set default worker, preload…

History.md

@@ -10,6 +10,12 @@
   * Changed #connected_port to #connected_ports (#2076)
   * `--control` has been removed. Use `--control-url` (#1487)
   * `worker_directory` has been removed. Use `directory`
+  * min_threads now set by environment variables RAILS_MIN_THREADS and MIN_THREADS
+  * max_threads now set by environment variables RAILS_MAX_THREADS and MAX_THREADS
+  * max_threads default to 5 in MRI or 16 for all other interpretters
+  * default to 1 worker if running on MRI or 0 if jruby/windows
+  * preload by default if workers > 1 and interpretter supports workers
+
 
 * Bugfixes
   * Windows update extconf.rb for use with ssp and varied Ruby/MSYS2 combinations (#2069)

lib/puma/configuration.rb

@@ -106,7 +106,7 @@ def finalize_values
   #
   # It also handles loading plugins.
   #
-  # > Note: `:port` and `:host` are not valid keys. By the time they make it to the
+  # > Note: `:port` and `:host` are not valid keys. By they time they make it to the
   #   configuration options they are expected to be incorporated into a `:binds` key.
   #   Under the hood the DSL maps `port` and `host` calls to `:binds`
   #
@@ -137,6 +137,8 @@ def initialize(user_options={}, default_options = {}, &block)
       @file_dsl    = DSL.new(@options.file_options, self)
       @default_dsl = DSL.new(@options.default_options, self)
 
+      default_options[:preload_app] = (default_options[:workers] > 1 && Puma::Plugin.new.workers_supported?)
+
       if block
         configure(&block)
       end
@@ -167,14 +169,24 @@ def flatten!
       self
     end
 
+    def default_workers
+      return 0 if Puma.jruby? || Puma.windows?
+      1
+    end
+
+    def default_max_threads
+      return 5 if RUBY_ENGINE.nil? || RUBY_ENGINE == 'ruby'
+      16
+    end
+
     def puma_default_options
       {
-        :min_threads => 0,
-        :max_threads => 16,
+        :min_threads => Integer(ENV['RAILS_MIN_THREADS'] || ENV['MIN_THREADS'] || 0),
+        :max_threads => Integer(ENV['RAILS_MAX_THREADS'] || ENV['MAX_THREADS'] || default_max_threads),
         :log_requests => false,
         :debug => false,
         :binds => ["tcp://#{DefaultTCPHost}:#{DefaultTCPPort}"],
-        :workers => 0,
+        :workers => Integer(ENV['WEB_CONCURRENCY'] || default_workers),
         :daemon => false,
         :mode => :http,
         :worker_timeout => DefaultWorkerTimeout,

test/test_config.rb

@@ -8,6 +8,64 @@
 class TestConfigFile < TestConfigFileBase
   parallelize_me!
 
+  def test_default_workers
+    workers = 1
+    workers = 0 if Puma.jruby? || Puma.windows?
+    assert_equal workers, Puma::Configuration.new.default_workers
+  end
+
+  def test_default_max_threads
+    max_threads = 16
+    max_threads = 5 if RUBY_ENGINE.nil? || RUBY_ENGINE == 'ruby'
+    assert_equal max_threads, Puma::Configuration.new.default_max_threads
+  end
+
+  def test_config_loads_correct_min_threads
+    conf = Puma::Configuration.new
+    assert_equal 0, conf.options.default_options[:min_threads]
+
+    ENV['MIN_THREADS'] = '7'
+    conf = Puma::Configuration.new
+    assert_equal 7, conf.options.default_options[:min_threads]
+
+    ENV['RAILS_MIN_THREADS'] = '8'
+    conf = Puma::Configuration.new
+    assert_equal 8, conf.options.default_options[:min_threads]
+  end
+
+  def test_config_loads_correct_max_threads
+    conf = Puma::Configuration.new
+    assert_equal conf.default_max_threads, conf.options.default_options[:max_threads]
+
+    ENV['MAX_THREADS'] = '7'
+    conf = Puma::Configuration.new
+    assert_equal 7, conf.options.default_options[:max_threads]
+
+    ENV['RAILS_MAX_THREADS'] = '8'
+    conf = Puma::Configuration.new
+    assert_equal 8, conf.options.default_options[:max_threads]
+  end
+
+  def test_config_loads_correct_workers
+    conf = Puma::Configuration.new
+    assert_equal conf.default_workers, conf.options.default_options[:workers]
+
+    ENV['WEB_CONCURRENCY'] = '8'
+    conf = Puma::Configuration.new
+    assert_equal 8, conf.options.default_options[:workers]
+  end
+
+  def test_config_preloads_app_if_using_workers
+    ENV['WEB_CONCURRENCY'] = '0'
+    conf = Puma::Configuration.new
+    assert_equal false, conf.options.default_options[:preload_app]
+
+    ENV['WEB_CONCURRENCY'] = '2'
+    preload = Puma::Plugin.new.workers_supported?
+    conf = Puma::Configuration.new
+    assert_equal preload, conf.options.default_options[:preload_app]
+  end
+
   def test_app_from_rackup
     conf = Puma::Configuration.new do |c|
       c.rackup "test/rackup/hello-bind.ru"