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 | 92 |
1 files changed, 73 insertions, 19 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 02a8f4e214..4297c26413 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb @@ -1,3 +1,4 @@ +require 'thread' require 'monitor' require 'set' require 'active_support/core_ext/module/synchronization' @@ -56,7 +57,9 @@ 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 + attr_accessor :automatic_reconnect attr_reader :spec, :connections + attr_reader :columns, :columns_hash, :primary_keys, :tables # Creates a new ConnectionPool object. +spec+ is a ConnectionSpecification # object which describes database connection information (e.g. adapter, @@ -73,18 +76,70 @@ module ActiveRecord # The mutex used to synchronize pool access @connection_mutex = Monitor.new @queue = @connection_mutex.new_cond - - # default 5 second timeout unless on ruby 1.9 - @timeout = - if RUBY_VERSION < '1.9' - spec.config[:wait_timeout] || 5 - end + @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 = [] + @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 + + @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 } + end + + @tables.key? name + end + + # Clears out internal caches: + # + # * columns + # * columns_hash + # * tables + def clear_cache! + @columns.clear + @columns_hash.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 + @primary_keys.delete table_name end # Retrieve the connection associated with the current thread, or call @@ -93,11 +148,7 @@ module ActiveRecord # #connection can be called any number of times; the connection is # held in a hash keyed by the thread id. def connection - if conn = @reserved_connections[current_connection_id] - conn - else - @reserved_connections[current_connection_id] = checkout - end + @reserved_connections[current_connection_id] ||= checkout end # Signal that the thread is finished with the current connection. @@ -109,7 +160,7 @@ module ActiveRecord end # If a connection already exists yield it to the block. If no connection - # exists checkout a connection, yield it to the block, and checkin the + # exists checkout a connection, yield it to the block, and checkin the # connection when finished. def with_connection connection_id = current_connection_id @@ -165,7 +216,6 @@ module ActiveRecord keys = @reserved_connections.keys - Thread.list.find_all { |t| t.alive? }.map { |thread| thread.object_id } - keys.each do |key| checkin @reserved_connections[key] @reserved_connections.delete(key) @@ -198,16 +248,18 @@ module ActiveRecord checkout_new_connection end return conn if conn - # No connections available; wait for one - if @queue.wait(@timeout) + + @queue.wait(@timeout) + + if(@checked_out.size < @connections.size) next else - # try looting dead threads clear_stale_cached_connections! if @size == @checked_out.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 + end end end @@ -219,7 +271,7 @@ module ActiveRecord # calling +checkout+ on this pool. def checkin(conn) @connection_mutex.synchronize do - conn.send(:_run_checkin_callbacks) do + conn.run_callbacks :checkin do @checked_out.delete conn @queue.signal end @@ -239,6 +291,8 @@ module ActiveRecord end def checkout_new_connection + raise ConnectionNotEstablished unless @automatic_reconnect + c = new_connection @connections << c checkout_and_verify(c) @@ -326,7 +380,7 @@ module ActiveRecord # already been opened. def connected?(klass) conn = retrieve_connection_pool(klass) - conn ? conn.connected? : false + conn && conn.connected? end # Remove the connection for this class. This will close the active @@ -337,7 +391,7 @@ module ActiveRecord pool = @connection_pools[klass.name] return nil unless pool - @connection_pools.delete_if { |key, value| value == pool } + pool.automatic_reconnect = false pool.disconnect! pool.spec.config end |