make keepalive_timeout configurable

And change the default to 2 seconds, most clients can
render the page and load all URLs within 2 seconds.

6 files changed, 22 insertions, 7 deletions

diff --git a/lib/rainbows.rb b/lib/rainbows.rb
index 4686f2b..3fed331 100644
--- a/lib/rainbows.rb
+++ b/lib/rainbows.rb
@@ -6,7 +6,7 @@ module Rainbows
   # global vars because class/instance variables are confusing me :<
   # this struct is only accessed inside workers and thus private to each
   # G.cur may not be used the network concurrency model
-  class State < Struct.new(:alive,:m,:cur,:server,:tmp)
+  class State < Struct.new(:alive,:m,:cur,:kato,:server,:tmp)
     def tick
       tmp.chmod(self.m = m == 0 ? 1 : 0)
       alive && server.master_pid == Process.ppid or quit!
@@ -18,7 +18,7 @@ module Rainbows
       false
     end
   end
-  G = State.new(true, 0, 0)
+  G = State.new(true, 0, 0, 2)
 
   require 'rainbows/const'
   require 'rainbows/http_server'
@@ -43,6 +43,7 @@ module Rainbows
   #   Rainbows! do
   #     use :Revactor # this may also be :ThreadSpawn or :ThreadPool
   #     worker_connections 400
+  #     keepalive_timeout 0 # zero disables keepalives entirely
   #   end
   #
   #   # the rest of the Unicorn configuration
@@ -53,6 +54,12 @@ module Rainbows
   # each of them.  The total number of clients we're able to serve is
   # +worker_processes+ * +worker_connections+, so in the above example
   # we can serve 8 * 400 = 3200 clients concurrently.
+  #
+  # The default is +keepalive_timeout+ is 2 seconds, which should be
+  # enough under most conditions for browsers to render the page and
+  # start retrieving extra elements for.  Increasing this beyond 5
+  # seconds is not recommended.  Zero disables keepalive entirely
+  # (but pipelining fully-formed requests is still works).
   def Rainbows!(&block)
     block_given? or raise ArgumentError, "Rainbows! requires a block"
     HttpServer.setup(block)
diff --git a/lib/rainbows/base.rb b/lib/rainbows/base.rb
index 62a7701..9a653ff 100644
--- a/lib/rainbows/base.rb
+++ b/lib/rainbows/base.rb
@@ -40,7 +40,7 @@ module Rainbows
 
       begin # loop
         while ! hp.headers(env, buf)
-          IO.select([client], nil, nil, 5) or return client.close
+          IO.select([client], nil, nil, G.kato) or return client.close
           buf << client.readpartial(CHUNK_SIZE)
         end
 
diff --git a/lib/rainbows/event_machine.rb b/lib/rainbows/event_machine.rb
index 056bdd5..54c1bc0 100644
--- a/lib/rainbows/event_machine.rb
+++ b/lib/rainbows/event_machine.rb
@@ -74,7 +74,7 @@ module Rainbows
             @state = :headers
             # keepalive requests are always body-less, so @input is unchanged
             @hp.headers(@env, @buf) and next
-            set_comm_inactivity_timeout 5
+            set_comm_inactivity_timeout G.kato
           end
           return
         end while true
diff --git a/lib/rainbows/http_server.rb b/lib/rainbows/http_server.rb
index c26285c..da97929 100644
--- a/lib/rainbows/http_server.rb
+++ b/lib/rainbows/http_server.rb
@@ -68,6 +68,11 @@ module Rainbows
       @worker_connections = nr
     end
 
+    def keepalive_timeout(nr)
+      (Integer === nr && nr >= 0) or
+        raise ArgumentError, "keepalive must be a non-negative Integer"
+      G.kato = nr
+    end
   end
 
 end
diff --git a/lib/rainbows/rev/heartbeat.rb b/lib/rainbows/rev/heartbeat.rb
index 5f76ed7..ee9d1b5 100644
--- a/lib/rainbows/rev/heartbeat.rb
+++ b/lib/rainbows/rev/heartbeat.rb
@@ -10,8 +10,10 @@ module Rainbows
     class Heartbeat < ::Rev::TimerWatcher
 
       def on_timer
-        ot = Time.now - 5
-        KATO.delete_if { |client, time| time < ot and client.timeout? }
+        if (ot = G.kato) > 0
+          ot = Time.now - ot
+          KATO.delete_if { |client, time| time < ot and client.timeout? }
+        end
         exit if (! G.tick && G.cur <= 0)
       end
 
diff --git a/lib/rainbows/revactor.rb b/lib/rainbows/revactor.rb
index 4cf6f11..489236c 100644
--- a/lib/rainbows/revactor.rb
+++ b/lib/rainbows/revactor.rb
@@ -23,7 +23,7 @@ module Rainbows
   module Revactor
     require 'rainbows/revactor/tee_input'
 
-    RD_ARGS = { :timeout => 5 }
+    RD_ARGS = {}
 
     include Base
 
@@ -75,6 +75,7 @@ module Rainbows
     # given a INT, QUIT, or TERM signal)
     def worker_loop(worker)
       init_worker_process(worker)
+      RD_ARGS[:timeout] = G.kato if G.kato > 0
 
       root = Actor.current
       root.trap_exit = true