diff options
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb | 59 | ||||
| -rw-r--r-- | activerecord/test/cases/connection_pool_test.rb | 24 |
2 files changed, 63 insertions, 20 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 561e48d52e..a609867898 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -2,6 +2,7 @@ require 'thread' require 'monitor' require 'set' require 'active_support/core_ext/module/deprecation' +require 'timeout' module ActiveRecord # Raised when a connection could not be obtained within the connection @@ -11,9 +12,6 @@ module ActiveRecord # Raised when a connection pool is full and another connection is requested class PoolFullError < ConnectionNotEstablished - def initialize size, timeout - super("Connection pool of size #{size} and timeout #{timeout}s is full") - end end module ConnectionAdapters @@ -94,6 +92,21 @@ module ActiveRecord attr_accessor :automatic_reconnect, :timeout attr_reader :spec, :connections, :size, :reaper + class Latch # :nodoc: + def initialize + @mutex = Mutex.new + @cond = ConditionVariable.new + end + + def release + @mutex.synchronize { @cond.broadcast } + end + + def await + @mutex.synchronize { @cond.wait @mutex } + end + end + # Creates a new ConnectionPool object. +spec+ is a ConnectionSpecification # object which describes database connection information (e.g. adapter, # host name, username, password, etc), as well as the maximum size for @@ -115,6 +128,7 @@ module ActiveRecord # default max pool size to 5 @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5 + @latch = Latch.new @connections = [] @automatic_reconnect = true end @@ -139,8 +153,10 @@ module ActiveRecord # #release_connection releases the connection-thread association # and returns the connection to the pool. def release_connection(with_id = current_connection_id) - conn = @reserved_connections.delete(with_id) - checkin conn if conn + synchronize do + conn = @reserved_connections.delete(with_id) + checkin conn if conn + end end # If a connection already exists yield it to the block. If no connection @@ -205,23 +221,23 @@ module ActiveRecord # Raises: # - PoolFullError: no connection can be obtained from the pool. def checkout - # Checkout an available connection - synchronize do - # Try to find a connection that hasn't been leased, and lease it - conn = connections.find { |c| c.lease } - - # If all connections were leased, and we have room to expand, - # create a new connection and lease it. - if !conn && connections.size < size - conn = checkout_new_connection - conn.lease - end + loop do + # Checkout an available connection + synchronize do + # Try to find a connection that hasn't been leased, and lease it + conn = connections.find { |c| c.lease } + + # If all connections were leased, and we have room to expand, + # create a new connection and lease it. + if !conn && connections.size < size + conn = checkout_new_connection + conn.lease + end - if conn - checkout_and_verify conn - else - raise PoolFullError.new(size, timeout) + return checkout_and_verify(conn) if conn end + + Timeout.timeout(@timeout, PoolFullError) { @latch.await } end end @@ -238,6 +254,7 @@ module ActiveRecord release conn end + @latch.release end # Remove a connection from the connection pool. The connection will @@ -250,6 +267,7 @@ module ActiveRecord # from the reserved hash will be a little easier. release conn end + @latch.release end # Removes dead connections from the pool. A dead connection can occur @@ -262,6 +280,7 @@ module ActiveRecord remove conn if conn.in_use? && stale > conn.last_use && !conn.active? end end + @latch.release end private diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb index da93500ce3..8dc9f761c2 100644 --- a/activerecord/test/cases/connection_pool_test.rb +++ b/activerecord/test/cases/connection_pool_test.rb @@ -96,6 +96,30 @@ module ActiveRecord end end + def test_full_pool_blocks + cs = @pool.size.times.map { @pool.checkout } + t = Thread.new { @pool.checkout } + + # make sure our thread is in the timeout section + Thread.pass until t.status == "sleep" + + connection = cs.first + connection.close + assert_equal connection, t.join.value + end + + def test_removing_releases_latch + cs = @pool.size.times.map { @pool.checkout } + t = Thread.new { @pool.checkout } + + # make sure our thread is in the timeout section + Thread.pass until t.status == "sleep" + + connection = cs.first + @pool.remove connection + assert_respond_to t.join.value, :execute + end + def test_reap_and_active @pool.checkout @pool.checkout |