diff options
6 files changed, 129 insertions, 17 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb index c5013dc1ee..9849f9d5d7 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -63,15 +63,13 @@ module ActiveRecord # There are several connection-pooling-related options that you can add to # your database connection configuration: # - # * +pool+: number indicating size of connection pool (default 5) - # * +checkout_timeout+: number of seconds to block and wait for a connection - # before giving up and raising a timeout error (default 5 seconds). - # * +reaping_frequency+: frequency in seconds to periodically run the - # Reaper, which attempts to find and recover connections from dead - # threads, which can occur if a programmer forgets to close a - # connection at the end of a thread or a thread dies unexpectedly. - # Regardless of this setting, the Reaper will be invoked before every - # blocking wait. (Default +nil+, which means don't schedule the Reaper). + # * +pool+: maximum number of connections the pool may manage (default 5). + # * +idle_timeout+: number of seconds that a connection will be kept + # unused in the pool before it is automatically disconnected (default + # 300 seconds). Set this to zero to keep connections forever. + # * +checkout_timeout+: number of seconds to wait for a connection to + # become available before giving up and raising a timeout error (default + # 5 seconds). # #-- # Synchronization policy: @@ -280,12 +278,12 @@ module ActiveRecord end end - # Every +frequency+ seconds, the reaper will call +reap+ on +pool+. - # A reaper instantiated with a +nil+ frequency will never reap the - # connection pool. + # Every +frequency+ seconds, the reaper will call +reap+ and +flush+ on + # +pool+. A reaper instantiated with a zero frequency will never reap + # the connection pool. # - # Configure the frequency by setting "reaping_frequency" in your - # database yaml file. + # Configure the frequency by setting +reaping_frequency+ in your database + # yaml file (default 60 seconds). class Reaper attr_reader :pool, :frequency @@ -295,11 +293,12 @@ module ActiveRecord end def run - return unless frequency + return unless frequency && frequency > 0 Thread.new(frequency, pool) { |t, p| loop do sleep t p.reap + p.flush end } end @@ -323,6 +322,10 @@ module ActiveRecord @spec = spec @checkout_timeout = (spec.config[:checkout_timeout] && spec.config[:checkout_timeout].to_f) || 5 + if @idle_timeout = spec.config.fetch(:idle_timeout, 300) + @idle_timeout = @idle_timeout.to_f + @idle_timeout = nil if @idle_timeout <= 0 + end # default max pool size to 5 @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5 @@ -353,7 +356,10 @@ module ActiveRecord @lock_thread = false - @reaper = Reaper.new(self, spec.config[:reaping_frequency] && spec.config[:reaping_frequency].to_f) + # +reaping_frequency+ is configurable mostly for historical reasons, but it could + # also be useful if someone wants a very low +idle_timeout+. + reaping_frequency = spec.config.fetch(:reaping_frequency, 60) + @reaper = Reaper.new(self, reaping_frequency && reaping_frequency.to_f) @reaper.run end @@ -587,6 +593,35 @@ module ActiveRecord end end + # Disconnect all connections that have been idle for at least + # +minimum_idle+ seconds. Connections currently checked out, or that were + # checked in less than +minimum_idle+ seconds ago, are unaffected. + def flush(minimum_idle = @idle_timeout) + return if minimum_idle.nil? + + idle_connections = synchronize do + @connections.select do |conn| + !conn.in_use? && conn.seconds_idle >= minimum_idle + end.each do |conn| + conn.lease + + @available.delete conn + @connections.delete conn + end + end + + idle_connections.each do |conn| + conn.disconnect! + end + end + + # Disconnect all currently idle connections. Connections currently checked + # out are unaffected. + def flush! + reap + flush(-1) + end + def num_waiting_in_queue # :nodoc: @available.num_waiting end @@ -956,6 +991,13 @@ module ActiveRecord connection_pool_list.each(&:disconnect!) end + # Disconnects all currently idle connections. + # + # See ConnectionPool#flush! for details. + def flush_idle_connections! + connection_pool_list.each(&:flush!) + end + # Locate the connection of the nearest super class. This can be an # active or defined connection: if it is the latter, it will be # opened and set as the active connection for the class it was defined diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb index 5411a6a262..8993c517a6 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb @@ -105,6 +105,7 @@ module ActiveRecord @logger = logger @config = config @pool = nil + @idle_since = Concurrent.monotonic_time @schema_cache = SchemaCache.new self @quoted_column_names, @quoted_table_names = {}, {} @visitor = arel_visitor @@ -164,6 +165,7 @@ module ActiveRecord "Current thread: #{Thread.current}." end + @idle_since = Concurrent.monotonic_time @owner = nil else raise ActiveRecordError, "Cannot expire connection, it is not currently leased." @@ -183,6 +185,12 @@ module ActiveRecord end end + # Seconds since this connection was returned to the pool + def seconds_idle # :nodoc: + return 0 if in_use? + Concurrent.monotonic_time - @idle_since + end + def unprepared_statement old_prepared_statements, @prepared_statements = @prepared_statements, false yield diff --git a/activerecord/lib/active_record/connection_handling.rb b/activerecord/lib/active_record/connection_handling.rb index 9a47edfba4..88d28dc52a 100644 --- a/activerecord/lib/active_record/connection_handling.rb +++ b/activerecord/lib/active_record/connection_handling.rb @@ -140,6 +140,6 @@ module ActiveRecord end delegate :clear_active_connections!, :clear_reloadable_connections!, - :clear_all_connections!, to: :connection_handler + :clear_all_connections!, :flush_idle_connections!, to: :connection_handler end end diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb index 812e1d7a00..9ee8425e1b 100644 --- a/activerecord/lib/active_record/railtie.rb +++ b/activerecord/lib/active_record/railtie.rb @@ -177,7 +177,16 @@ end_warning initializer "active_record.clear_active_connections" do config.after_initialize do ActiveSupport.on_load(:active_record) do + # Ideally the application doesn't connect to the database during boot, + # but sometimes it does. In case it did, we want to empty out the + # connection pools so that a non-database-using process (e.g. a master + # process in a forking server model) doesn't retain a needless + # connection. If it was needed, the incremental cost of reestablishing + # this connection is trivial: the rest of the pool would need to be + # populated anyway. + clear_active_connections! + flush_idle_connections! end end end diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb index cb2fefb4f6..1e08cc74dc 100644 --- a/activerecord/test/cases/connection_pool_test.rb +++ b/activerecord/test/cases/connection_pool_test.rb @@ -156,6 +156,53 @@ module ActiveRecord @pool.connections.each { |conn| conn.close if conn.in_use? } end + def test_flush + idle_conn = @pool.checkout + recent_conn = @pool.checkout + active_conn = @pool.checkout + + @pool.checkin idle_conn + @pool.checkin recent_conn + + assert_equal 3, @pool.connections.length + + def idle_conn.seconds_idle + 1000 + end + + @pool.flush(30) + + assert_equal 2, @pool.connections.length + + assert_equal [recent_conn, active_conn].sort_by(&:__id__), @pool.connections.sort_by(&:__id__) + ensure + @pool.checkin active_conn + end + + def test_flush_bang + idle_conn = @pool.checkout + recent_conn = @pool.checkout + active_conn = @pool.checkout + _dead_conn = Thread.new { @pool.checkout }.join + + @pool.checkin idle_conn + @pool.checkin recent_conn + + assert_equal 4, @pool.connections.length + + def idle_conn.seconds_idle + 1000 + end + + @pool.flush! + + assert_equal 1, @pool.connections.length + + assert_equal [active_conn].sort_by(&:__id__), @pool.connections.sort_by(&:__id__) + ensure + @pool.checkin active_conn + end + def test_remove_connection conn = @pool.checkout assert conn.in_use? diff --git a/activerecord/test/cases/reaper_test.rb b/activerecord/test/cases/reaper_test.rb index 49170abe6f..6c7727ab1b 100644 --- a/activerecord/test/cases/reaper_test.rb +++ b/activerecord/test/cases/reaper_test.rb @@ -18,6 +18,7 @@ module ActiveRecord class FakePool attr_reader :reaped + attr_reader :flushed def initialize @reaped = false @@ -26,6 +27,10 @@ module ActiveRecord def reap @reaped = true end + + def flush + @flushed = true + end end # A reaper with nil time should never reap connections @@ -47,6 +52,7 @@ module ActiveRecord Thread.pass end assert fp.reaped + assert fp.flushed end def test_pool_has_reaper |