Commit e9799ba6 authored by unknown's avatar unknown
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ha_innodb.cc: 

  Weaken InnoDB table locking at the start of a stored procedure call: this will make multi-transaction stored procedures less deterministic for binlogging, but since they are non-deterministic anyway, it is not that bad; this fix will remove the huge amount of InnoDB tranasctional deadlocks caused by table locking at the start of a stored procedure


sql/ha_innodb.cc:
  Weaken InnoDB table locking at the start of a stored procedure call: this will make multi-transaction stored procedures less deterministic for binlogging, but since they are non-deterministic anyway, it is not that bad; this fix will remove the huge amount of InnoDB tranasctional deadlocks caused by table locking at the start of a stored procedure
parent 55efc0e2

sql/ha_innodb.cc

+19 −3
Original line number Diff line number Diff line
@@ -5963,11 +5963,14 @@ ha_innobase::external_lock( 
		TABLES if AUTOCOMMIT=1. It does not make much sense to acquire

		an InnoDB table lock if it is released immediately at the end

		of LOCK TABLES, and InnoDB's table locks in that case cause

		VERY easily deadlocks. */

		VERY easily deadlocks. We do not set InnoDB table locks when

		MySQL sets them at the start of a stored procedure call

		(MySQL does have thd->in_lock_tables TRUE there). */



		if (prebuilt->select_lock_type != LOCK_NONE) {



			if (thd->in_lock_tables &&

			    thd->lex->sql_command != SQLCOM_CALL &&

			    thd->variables.innodb_table_locks &&

			    (thd->options & OPTION_NOT_AUTOCOMMIT)) {
@@ -6478,11 +6481,21 @@ ha_innobase::store_lock( 


	if (lock_type != TL_IGNORE && lock.type == TL_UNLOCK) {



		/* Starting from 5.0.7, we weaken also the table locks

		set at the start of a MySQL stored procedure call, just like

		we weaken the locks set at the start of an SQL statement.

		MySQL does set thd->in_lock_tables TRUE there, but in reality

		we do not need table locks to make the execution of a

		single transaction stored procedure call deterministic

		(if it does not use a consistent read). */



    		/* If we are not doing a LOCK TABLE or DISCARD/IMPORT

		TABLESPACE or TRUNCATE TABLE, then allow multiple writers */



    		if ((lock_type >= TL_WRITE_CONCURRENT_INSERT &&

	 	    lock_type <= TL_WRITE) && !thd->in_lock_tables

	 	    lock_type <= TL_WRITE)

		    && (!thd->in_lock_tables

		        || thd->lex->sql_command == SQLCOM_CALL)

		    && !thd->tablespace_op

		    && thd->lex->sql_command != SQLCOM_TRUNCATE

                    && thd->lex->sql_command != SQLCOM_CREATE_TABLE) {
@@ -6496,7 +6509,10 @@ ha_innobase::store_lock( 
		to t2. Convert the lock to a normal read lock to allow

		concurrent inserts to t2. */

      		

		if (lock_type == TL_READ_NO_INSERT && !thd->in_lock_tables) {

		if (lock_type == TL_READ_NO_INSERT

		    && (!thd->in_lock_tables

			|| thd->lex->sql_command == SQLCOM_CALL)) {



			lock_type = TL_READ;

		}