add client_header_buffer_size tuning parameter

We're changing our default to 1K buffers to save memory.  This
should reduce memory usage of idle clients and lower pressure on
the MRI GC.  Rails applications using session cookies (the
default) may want to up this to 2K or more.

8 files changed, 19 insertions, 9 deletions

diff --git a/lib/rainbows/client.rb b/lib/rainbows/client.rb
index 7387c44..4608f53 100644
--- a/lib/rainbows/client.rb
+++ b/lib/rainbows/client.rb
@@ -4,6 +4,8 @@ require "io/wait"
 
 # this class is used for most synchronous concurrency models
 class Rainbows::Client < Kgio::Socket
+  include Rainbows::ProcessClient
+
   def read_expire
     Time.now + Rainbows.keepalive_timeout
   end
@@ -16,7 +18,7 @@ class Rainbows::Client < Kgio::Socket
   def timed_read(buf)
     expire = nil
     begin
-      case rv = kgio_tryread(0x1000, buf)
+      case rv = kgio_tryread(HBUFSIZ, buf)
       when :wait_readable
         return if expire && expire < Time.now
         expire ||= read_expire
@@ -26,6 +28,4 @@ class Rainbows::Client < Kgio::Socket
       end
     end while true
   end
-
-  include Rainbows::ProcessClient
 end
diff --git a/lib/rainbows/configurator.rb b/lib/rainbows/configurator.rb
index 3203c5a..b596b0b 100644
--- a/lib/rainbows/configurator.rb
+++ b/lib/rainbows/configurator.rb
@@ -14,6 +14,7 @@ module Rainbows::Configurator
   #     keepalive_timeout 0 # zero disables keepalives entirely
   #     client_max_body_size 5*1024*1024 # 5 megabytes
   #     keepalive_requests 666 # default:100
+  #     client_header_buffer_size 16 * 1024 # 16 kilobytes
   #   end
   #
   #   # the rest of the Unicorn configuration
diff --git a/lib/rainbows/coolio/client.rb b/lib/rainbows/coolio/client.rb
index 2de421a..5688730 100644
--- a/lib/rainbows/coolio/client.rb
+++ b/lib/rainbows/coolio/client.rb
@@ -45,7 +45,7 @@ class Rainbows::Coolio::Client < Coolio::IO
   end
 
   def on_readable
-    buf = @_io.kgio_tryread(16384, RBUF)
+    buf = @_io.kgio_tryread(HBUFSIZ, RBUF)
     case buf
     when :wait_readable
     when nil # eof
@@ -134,7 +134,7 @@ class Rainbows::Coolio::Client < Coolio::IO
       close if @_write_buffer.empty?
     when :headers
       if @buf.empty?
-        buf = @_io.kgio_tryread(16384, RBUF) or return close
+        buf = @_io.kgio_tryread(HBUFSIZ, RBUF) or return close
         String === buf and return on_read(buf)
         # buf == :wait_readable
         unless enabled?
diff --git a/lib/rainbows/epoll/client.rb b/lib/rainbows/epoll/client.rb
index 924d32f..3fbd386 100644
--- a/lib/rainbows/epoll/client.rb
+++ b/lib/rainbows/epoll/client.rb
@@ -33,7 +33,7 @@ module Rainbows::Epoll::Client
   end
 
   def on_readable
-    case rv = kgio_tryread(16384, RBUF)
+    case rv = kgio_tryread(HBUFSIZ, RBUF)
     when String
       on_read(rv)
       return if @wr_queue[0] || closed?
diff --git a/lib/rainbows/ev_core.rb b/lib/rainbows/ev_core.rb
index 61853ab..24254dc 100644
--- a/lib/rainbows/ev_core.rb
+++ b/lib/rainbows/ev_core.rb
@@ -9,6 +9,7 @@ module Rainbows::EvCore
   autoload :CapInput, 'rainbows/ev_core/cap_input'
   RBUF = ""
   Z = "".freeze
+  HBUFSIZ = Rainbows.client_header_buffer_size
 
   # Apps may return this Rack response: AsyncResponse = [ -1, {}, [] ]
   ASYNC_CALLBACK = "async.callback".freeze
diff --git a/lib/rainbows/http_server.rb b/lib/rainbows/http_server.rb
index 4e1d7d9..c36b7bf 100644
--- a/lib/rainbows/http_server.rb
+++ b/lib/rainbows/http_server.rb
@@ -141,4 +141,10 @@ class Rainbows::HttpServer < Unicorn::HttpServer
     end
     Rainbows.max_bytes = nr
   end
+
+  def client_header_buffer_size(bytes)
+    Integer === bytes && bytes > 0 or raise ArgumentError,
+            "client_header_buffer_size must be a positive Integer"
+    Rainbows.client_header_buffer_size = bytes
+  end
 end
diff --git a/lib/rainbows/process_client.rb b/lib/rainbows/process_client.rb
index 6201064..f30aa5d 100644
--- a/lib/rainbows/process_client.rb
+++ b/lib/rainbows/process_client.rb
@@ -7,10 +7,11 @@ module Rainbows::ProcessClient
   NULL_IO = Unicorn::HttpRequest::NULL_IO
   RACK_INPUT = Unicorn::HttpRequest::RACK_INPUT
   IC = Unicorn::HttpRequest.input_class
+  HBUFSIZ = Rainbows.client_header_buffer_size
 
   def process_loop
     @hp = hp = Rainbows::HttpParser.new
-    kgio_read!(0x1000, buf = hp.buf) or return
+    kgio_read!(HBUFSIZ, buf = hp.buf) or return
 
     begin # loop
       until env = hp.parse
diff --git a/lib/rainbows/xepoll_thread_spawn/client.rb b/lib/rainbows/xepoll_thread_spawn/client.rb
index 9bee1d1..4111f27 100644
--- a/lib/rainbows/xepoll_thread_spawn/client.rb
+++ b/lib/rainbows/xepoll_thread_spawn/client.rb
@@ -4,6 +4,7 @@ require "sleepy_penguin"
 require "raindrops"
 
 module Rainbows::XEpollThreadSpawn::Client
+  HBUFSIZ = Rainbows.client_header_buffer_size
   N = Raindrops.new(1)
   max = Rainbows.server.worker_connections
   ACCEPTORS = Rainbows::HttpServer::LISTENERS.map do |sock|
@@ -88,7 +89,7 @@ module Rainbows::XEpollThreadSpawn::Client
   end
 
   def epoll_run(buf)
-    case kgio_tryread(0x1000, buf)
+    case kgio_tryread(HBUFSIZ, buf)
     when :wait_readable
       return kato_set
     when String
@@ -108,7 +109,7 @@ module Rainbows::XEpollThreadSpawn::Client
 
   def pipeline_ready(hp)
     env = hp.parse and return env
-    case buf = kgio_tryread(0x1000)
+    case buf = kgio_tryread(HBUFSIZ)
     when :wait_readable
       kato_set
       return false