diff options
Diffstat (limited to 'activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb')
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb | 219 |
1 files changed, 98 insertions, 121 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 ddfdb05297..698da34d26 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -1,7 +1,7 @@ require 'thread' require 'monitor' require 'set' -require 'active_support/core_ext/module/synchronization' +require 'active_support/core_ext/module/deprecation' module ActiveRecord # Raised when a connection could not be obtained within the connection @@ -57,10 +57,10 @@ module ActiveRecord # * +wait_timeout+: number of seconds to block and wait for a connection # before giving up and raising a timeout error (default 5 seconds). class ConnectionPool + include MonitorMixin + attr_accessor :automatic_reconnect attr_reader :spec, :connections - attr_reader :columns, :columns_hash, :primary_keys, :tables - attr_reader :column_defaults # Creates a new ConnectionPool object. +spec+ is a ConnectionSpecification # object which describes database connection information (e.g. adapter, @@ -69,87 +69,21 @@ module ActiveRecord # # The default ConnectionPool maximum size is 5. def initialize(spec) + super() + @spec = spec # The cache of reserved connections mapped to threads @reserved_connections = {} - # The mutex used to synchronize pool access - @connection_mutex = Monitor.new - @queue = @connection_mutex.new_cond + @queue = new_cond @timeout = spec.config[:wait_timeout] || 5 # default max pool size to 5 @size = (spec.config[:pool] && spec.config[:pool].to_i) || 5 - @connections = [] - @checked_out = [] + @connections = [] @automatic_reconnect = true - @tables = {} - - @columns = Hash.new do |h, table_name| - h[table_name] = with_connection do |conn| - - # Fetch a list of columns - conn.columns(table_name, "#{table_name} Columns").tap do |columns| - - # set primary key information - columns.each do |column| - column.primary = column.name == primary_keys[table_name] - end - end - end - end - - @columns_hash = Hash.new do |h, table_name| - h[table_name] = Hash[columns[table_name].map { |col| - [col.name, col] - }] - end - - @column_defaults = Hash.new do |h, table_name| - h[table_name] = Hash[columns[table_name].map { |col| - [col.name, col.default] - }] - end - - @primary_keys = Hash.new do |h, table_name| - h[table_name] = with_connection do |conn| - table_exists?(table_name) ? conn.primary_key(table_name) : 'id' - end - end - end - - # A cached lookup for table existence. - def table_exists?(name) - return true if @tables.key? name - - with_connection do |conn| - conn.tables.each { |table| @tables[table] = true } - @tables[name] = true if !@tables.key?(name) && conn.table_exists?(name) - end - - @tables.key? name - end - - # Clears out internal caches: - # - # * columns - # * columns_hash - # * tables - def clear_cache! - @columns.clear - @columns_hash.clear - @column_defaults.clear - @tables.clear - end - - # Clear out internal caches for table with +table_name+. - def clear_table_cache!(table_name) - @columns.delete table_name - @columns_hash.delete table_name - @column_defaults.delete table_name - @primary_keys.delete table_name end # Retrieve the connection associated with the current thread, or call @@ -164,7 +98,7 @@ module ActiveRecord # Check to see if there is an active connection in this connection # pool. def active_connection? - @reserved_connections.key? current_connection_id + active_connections.any? end # Signal that the thread is finished with the current connection. @@ -180,7 +114,7 @@ module ActiveRecord # connection when finished. def with_connection connection_id = current_connection_id - fresh_connection = true unless @reserved_connections[connection_id] + fresh_connection = true unless active_connection? yield connection ensure release_connection(connection_id) if fresh_connection @@ -188,43 +122,73 @@ module ActiveRecord # Returns true if a connection has already been opened. def connected? - !@connections.empty? + synchronize { @connections.any? } end # Disconnects all connections in the pool, and clears the pool. def disconnect! - @reserved_connections.each do |name,conn| - checkin conn - end - @reserved_connections = {} - @connections.each do |conn| - conn.disconnect! + synchronize do + @reserved_connections = {} + @connections.each do |conn| + checkin conn + conn.disconnect! + end + @connections = [] end - @connections = [] end # Clears the cache which maps classes. def clear_reloadable_connections! - @reserved_connections.each do |name, conn| - checkin conn - end - @reserved_connections = {} - @connections.each do |conn| - conn.disconnect! if conn.requires_reloading? - end - @connections.delete_if do |conn| - conn.requires_reloading? + synchronize do + @reserved_connections = {} + @connections.each do |conn| + checkin conn + conn.disconnect! if conn.requires_reloading? + end + @connections.delete_if do |conn| + conn.requires_reloading? + end end end # Verify active connections and remove and disconnect connections # associated with stale threads. def verify_active_connections! #:nodoc: - clear_stale_cached_connections! - @connections.each do |connection| - connection.verify! + synchronize do + clear_stale_cached_connections! + @connections.each do |connection| + connection.verify! + end + end + end + + def columns + with_connection do |c| + c.schema_cache.columns + end + end + deprecate :columns + + def columns_hash + with_connection do |c| + c.schema_cache.columns_hash + end + end + deprecate :columns_hash + + def primary_keys + with_connection do |c| + c.schema_cache.primary_keys + end + end + deprecate :primary_keys + + def clear_cache! + with_connection do |c| + c.schema_cache.clear! end end + deprecate :clear_cache! # Return any checked-out connections back to the pool by threads that # are no longer alive. @@ -233,7 +197,13 @@ module ActiveRecord t.alive? }.map { |thread| thread.object_id } keys.each do |key| - checkin @reserved_connections[key] + conn = @reserved_connections[key] + ActiveSupport::Deprecation.warn(<<-eowarn) if conn.in_use? +Database connections will not be closed automatically, please close your +database connection at the end of the thread by calling `close` on your +connection. For example: ActiveRecord::Base.connection.close + eowarn + checkin conn @reserved_connections.delete(key) end end @@ -256,22 +226,29 @@ module ActiveRecord # within the timeout period. def checkout # Checkout an available connection - @connection_mutex.synchronize do + synchronize do loop do - conn = if @checked_out.size < @connections.size - checkout_existing_connection - elsif @connections.size < @size - checkout_new_connection - end - return conn if conn + conn = @connections.find { |c| c.lease } + + unless conn + if @connections.size < @size + conn = checkout_new_connection + conn.lease + end + end + + if conn + checkout_and_verify conn + return conn + end @queue.wait(@timeout) - if(@checked_out.size < @connections.size) + if(active_connections.size < @connections.size) next else clear_stale_cached_connections! - if @size == @checked_out.size + if @size == active_connections.size raise ConnectionTimeoutError, "could not obtain a database connection#{" within #{@timeout} seconds" if @timeout}. The max pool size is currently #{@size}; consider increasing it." end end @@ -286,46 +263,43 @@ module ActiveRecord # +conn+: an AbstractAdapter object, which was obtained by earlier by # calling +checkout+ on this pool. def checkin(conn) - @connection_mutex.synchronize do + synchronize do conn.run_callbacks :checkin do - @checked_out.delete conn + conn.expire @queue.signal end end end - synchronize :clear_reloadable_connections!, :verify_active_connections!, - :connected?, :disconnect!, :with => :@connection_mutex - private + def new_connection ActiveRecord::Base.send(spec.adapter_method, spec.config) end def current_connection_id #:nodoc: - Thread.current.object_id + ActiveRecord::Base.connection_id ||= Thread.current.object_id end def checkout_new_connection raise ConnectionNotEstablished unless @automatic_reconnect c = new_connection + c.pool = self @connections << c - checkout_and_verify(c) - end - - def checkout_existing_connection - c = (@connections - @checked_out).first - checkout_and_verify(c) + c end def checkout_and_verify(c) c.run_callbacks :checkout do c.verify! - @checked_out << c end c end + + def active_connections + @connections.find_all { |c| c.in_use? } + end end # ConnectionHandler is a collection of ConnectionPool objects. It is used @@ -356,10 +330,12 @@ module ActiveRecord def initialize(pools = {}) @connection_pools = pools + @class_to_pool = {} end def establish_connection(name, spec) - @connection_pools[name] = ConnectionAdapters::ConnectionPool.new(spec) + @connection_pools[spec] ||= ConnectionAdapters::ConnectionPool.new(spec) + @class_to_pool[name] = @connection_pools[spec] end # Returns true if there are any active connections among the connection @@ -410,16 +386,17 @@ module ActiveRecord # can be used as an argument for establish_connection, for easily # re-establishing the connection. def remove_connection(klass) - pool = @connection_pools[klass.name] + pool = @class_to_pool.delete(klass.name) return nil unless pool + @connection_pools.delete pool.spec pool.automatic_reconnect = false pool.disconnect! pool.spec.config end def retrieve_connection_pool(klass) - pool = @connection_pools[klass.name] + pool = @class_to_pool[klass.name] return pool if pool return nil if ActiveRecord::Base == klass retrieve_connection_pool klass.superclass |