improved load balancing between Hypnotoad worker processes

mojolicious · Jul 5, 2012 · 5fa2485 · 5fa2485
1 parent 060c1a4
commit 5fa2485
Show file tree

Hide file tree

Showing 3 changed files with 11 additions and 6 deletions.
diff --git a/Changes b/Changes
@@ -1,5 +1,6 @@
 
 3.03  2012-07-06
+  - Improved load balancing between Hypnotoad worker processes.
   - Improved Hypnotoad log messages.
   - Improved documentation.
   - Improved tests.

diff --git a/lib/Mojo/IOLoop.pm b/lib/Mojo/IOLoop.pm
@@ -137,9 +137,11 @@ sub server {
       my $id     = $self->stream($stream);
       $self->$cb($stream, $id);
 
-      # Enforce connection limit
-      $self->max_connections(0)
-        if defined $self->{accepts} && --$self->{accepts} == 0;
+      # Enforce connection limit (randomize to improve load balancing)
+      if (defined $self->{accepts}) {
+        $self->{accepts} -= int(rand 2) ? 1 : 2;
+        $self->max_connections(0) if $self->{accepts} <= 0;
+      }
 
       # Stop listening
       $self->_not_listening;
@@ -397,7 +399,8 @@ this callback are not captured.
 The maximum number of connections this loop is allowed to accept before
 shutting down gracefully without interrupting existing connections, defaults
 to C<0>. Setting the value to C<0> will allow this loop to accept new
-connections indefinitely.
+connections indefinitely. Note that half of this value can be subtracted
+randomly to improve load balancing between multiple server processes.
 
 =head2 C<max_connections>
 

diff --git a/lib/Mojo/Server/Hypnotoad.pm b/lib/Mojo/Server/Hypnotoad.pm
@@ -460,8 +460,9 @@ L<Mojolicious::Guides::Cookbook/"Hypnotoad"> for examples.
 
 Maximum number of connections a worker is allowed to accept before stopping
 gracefully, defaults to C<1000>. Setting the value to C<0> will allow workers
-to accept new connections indefinitely. Note that worker processes stop
-sending heartbeat messages once this limit has been reached.
+to accept new connections indefinitely. Note that half of this value can be
+subtracted randomly to improve load balancing, and that worker processes will
+stop sending heartbeat messages once the limit has been reached.
 
 =head2 C<backlog>