RUBY-320 ReplSetConnection now caches tags and maps them to pools for reading.

lib/mongo/node.rb

@@ -12,6 +12,7 @@ module Mongo
         self.port = data[1].nil? ? Connection::DEFAULT_PORT : data[1].to_i
       end
       self.address = "#{host}:#{port}"
+      self.config = nil
     end
 
     def eql?(other)
@@ -98,7 +99,7 @@ module Mongo
     # Note: this excludes arbiters.
     def node_list
       connect unless connected?
-      set_config
+      set_config unless self.config
 
       return [] unless config
 
@@ -110,6 +111,7 @@ module Mongo
 
     def arbiters
       connect unless connected?
+      set_config unless self.config
       return [] unless config['arbiters']
 
       config['arbiters'].map do |arbiter|
@@ -117,6 +119,14 @@ module Mongo
       end
     end
 
+    def tags
+      connect unless connected?
+      set_config unless self.config
+      return {} unless config['tags'] && !config['tags'].empty?
+
+      config['tags']
+    end
+
     def primary?
       self.config['ismaster'] == true || self.config['ismaster'] == 1
     end

lib/mongo/repl_set_connection.rb

@@ -21,7 +21,7 @@ module Mongo
   # Instantiates and manages connections to a MongoDB replica set.
   class ReplSetConnection < Connection
     attr_reader :nodes, :secondaries, :arbiters, :secondary_pools,
-      :replica_set_name, :read_pool, :seeds
+      :replica_set_name, :read_pool, :seeds, :tags_to_pools
 
     # Create a connection to a MongoDB replica set.
     #
@@ -172,6 +172,7 @@ module Mongo
       @primary_pool = manager.primary_pool
       @read_pool    = manager.read_pool
       @secondary_pools = manager.secondary_pools
+      @tags_to_pools   = manager.tags_to_pools
       @seeds = manager.seeds
       @manager = manager
       @hosts = manager.hosts
@@ -334,9 +335,10 @@ module Mongo
     # an exception.
     def checkout_tagged(tags)
       tags.each do |k, v|
-        if pool = @tags_to_pools[{k.to_s => v}]
+        pools = @tags_to_pools[{k => v}]
-          socket = pool.checkout
+        if !pools.empty?
-          @sockets_to_pools[socket] = pool
+          socket = pools.first.checkout
+          @sockets_to_pools[socket] = pools.first
           return socket
         end
       end

lib/mongo/util/pool.rb

@@ -47,6 +47,8 @@ module Mongo
       @sockets      = []
       @pids         = {}
       @checked_out  = []
+      @ping_time    = nil
+      @last_ping    = nil
     end
 
     def close
@@ -71,9 +73,23 @@ module Mongo
       [@host, @port]
     end
 
+    # Refresh ping time only if we haven't
+    # checked within the last five minutes.
+    def ping_time
+      if !@last_ping
+        @last_ping = Time.now
+        @ping_time = refresh_ping_time
+      elsif Time.now - @last_ping > 300
+        @last_ping = Time.now
+        @ping_time = refresh_ping_time
+      else
+        @ping_time
+      end
+    end
+
     # Return the time it takes on average
     # to do a round-trip against this node.
-    def ping_time
+    def refresh_ping_time
       trials = []
       begin
          PING_ATTEMPTS.times do
@@ -86,13 +102,15 @@ module Mongo
       end
 
       trials.sort!
+
+      # Delete shortest and longest times
       trials.delete_at(trials.length-1)
       trials.delete_at(0)
 
       total = 0.0
       trials.each { |t| total += t }
 
-      (total / trials.length).floor
+      (total / trials.length).ceil
     end
 
     # Return a socket to the pool.

lib/mongo/util/pool_manager.rb

@@ -2,7 +2,8 @@ module Mongo
   class PoolManager
 
     attr_reader :connection, :seeds, :arbiters, :primary, :secondaries,
-      :primary_pool, :read_pool, :secondary_pools, :hosts, :nodes, :max_bson_size
+      :primary_pool, :read_pool, :secondary_pools, :hosts, :nodes, :max_bson_size,
+      :tags_to_pools
 
     def initialize(connection, seeds)
       @connection = connection
@@ -85,8 +86,6 @@ module Mongo
 
     private
 
-    # Note that @arbiters and @read_pool will be
-    # assigned automatically.
     def reference_manager_data(manager)
       @primary = manager.primary
       @primary_pool = manager.primary_pool
@@ -106,6 +105,7 @@ module Mongo
       @secondary_pools = []
       @hosts = []
       @members = []
+      @tags_to_pools = {}
     end
 
     # Connect to each member of the replica set
@@ -130,6 +130,23 @@ module Mongo
       members
     end
 
+    def associate_tags_with_pool(tags, pool)
+      tags.each_key do |key|
+        @tags_to_pools[{key => tags[key]}] ||= []
+        @tags_to_pools[{key => tags[key]}] << pool
+      end
+    end
+
+    # Sort each tag pool entry in descending order
+    # according to ping time.
+    def sort_tag_pools!
+      @tags_to_pools.each_value do |pool_list|
+        pool_list.sort! do |a, b|
+          a.ping_time <=> b.ping_time
+        end
+      end
+    end
+
     # Initialize the connection pools for the primary and secondary nodes.
     def initialize_pools(members)
       members.each do |member|
@@ -141,15 +158,19 @@ module Mongo
                                   :size => self.connection.pool_size,
                                   :timeout => self.connection.connect_timeout,
                                   :node => member)
+          associate_tags_with_pool(member.tags, @primary_pool)
         elsif member.secondary? && !@secondaries.include?(member.host_port)
           @secondaries << member.host_port
-          @secondary_pools << Pool.new(self.connection, member.host, member.port,
+          pool = Pool.new(self.connection, member.host, member.port,
                                        :size => self.connection.pool_size,
                                        :timeout => self.connection.connect_timeout,
                                        :node => member)
+          @secondary_pools << pool
+          associate_tags_with_pool(member.tags, pool)
         end
       end
 
+      sort_tag_pools!
       @max_bson_size = members.first.config['maxBsonObjectSize'] ||
         Mongo::DEFAULT_MAX_BSON_SIZE
       @arbiters = members.first.arbiters

test/tools/repl_set_manager.rb

@@ -10,7 +10,7 @@ end
 
 class ReplSetManager
 
-  attr_accessor :host, :start_port, :ports, :name, :mongods
+  attr_accessor :host, :start_port, :ports, :name, :mongods, :tags, :version
 
   def initialize(opts={})
     @start_port = opts[:start_port] || 30000
@@ -21,6 +21,10 @@ class ReplSetManager
     @config     = {"_id" => @name, "members" => []}
     @durable    = opts.fetch(:durable, false)
     @path       = File.join(File.expand_path(File.dirname(__FILE__)), "data")
+    @oplog_size = opts.fetch(:oplog_size, 512)
+    @tags = [{"dc" => "ny", "rack" => "a", "db" => "main"},
+             {"dc" => "ny", "rack" => "b", "db" => "main"},
+             {"dc" => "sf", "rack" => "a", "db" => "main"}]
 
     @arbiter_count   = opts[:arbiter_count]   || 2
     @secondary_count = opts[:secondary_count] || 2
@@ -33,6 +37,9 @@ class ReplSetManager
     end
 
     @mongods   = {}
+    version_string = `mongod --version`
+    version_string =~ /(\d\.\d\.\d)/
+    @version = $1.split(".").map {|d| d.to_i }
   end
 
   def start_set
@@ -42,7 +49,11 @@ class ReplSetManager
 
     n = 0
     (@primary_count + @secondary_count).times do
-      init_node(n)
+      init_node(n) do |attrs|
+        if @version[0] >= 2
+          attrs['tags'] = @tags[n % @tags.size]
+        end
+      end
       n += 1
     end
 
@@ -96,9 +107,21 @@ class ReplSetManager
     @config['members'] << member
   end
 
+  def journal_switch
+    if @version[0] >= 2
+      if @durable
+        "--journal"
+      else
+        "--nojournal"
+      end
+    elsif @durable
+      "--journal"
+    end
+  end
+
   def start_cmd(n)
     @mongods[n]['start'] = "mongod --replSet #{@name} --logpath '#{@mongods[n]['log_path']}' " +
-     " --dbpath #{@mongods[n]['db_path']} --port #{@mongods[n]['port']} --fork"
+     "--oplogSize #{@oplog_size} #{journal_switch} --dbpath #{@mongods[n]['db_path']} --port #{@mongods[n]['port']} --fork"
     @mongods[n]['start'] += " --dur" if @durable
     @mongods[n]['start']
   end