# # Test of the cost constants when restarting the server # # To get stable cost estimates, the test should only be run with # 16K InnoDB page size. # # Test that changes to cost constants are used after restarting server # # Verify that the content of the two cost constants tables are as expected SELECT cost_name,cost_value FROM mysql.server_cost; SELECT engine_name,cost_name,cost_value FROM mysql.engine_cost; # # Create a test database that will be used for running queries # CREATE TABLE t0 ( i1 INTEGER ); INSERT INTO t0 VALUE (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); # Create a table with 100 records each having size approximately 1000 bytes CREATE TABLE t1_innodb ( pk INTEGER PRIMARY KEY, i1 INTEGER NOT NULL, c1 CHAR(250), c2 CHAR(250), c3 CHAR(250), c4 CHAR(250), INDEX i1_key (i1) ) ENGINE=InnoDB; INSERT INTO t1_innodb SELECT a0.i1 + 10 * a1.i1, a0.i1, 'abc', 'def', 'ghi', 'jkl' FROM t0 AS a0, t0 AS a1; # Create the same table in MyISAM CREATE TABLE t1_myisam ( pk INTEGER PRIMARY KEY, i1 INTEGER NOT NULL, c1 CHAR(250), c2 CHAR(250), c3 CHAR(250), c4 CHAR(250), INDEX i1_key (i1) ) ENGINE=MyISAM; INSERT INTO t1_myisam SELECT a0.i1 + 10 * a1.i1, a0.i1, 'abc', 'def', 'ghi', 'jkl' FROM t0 AS a0, t0 AS a1; # Create the same table in XEngine CREATE TABLE t1_xengine ( pk INTEGER PRIMARY KEY, i1 INTEGER NOT NULL, c1 CHAR(250), c2 CHAR(250), c3 CHAR(250), c4 CHAR(250), INDEX i1_key (i1) ) ENGINE=XENGINE; INSERT INTO t1_xengine SELECT a0.i1 + 10 * a1.i1, a0.i1, 'abc', 'def', 'ghi', 'jkl' FROM t0 AS a0, t0 AS a1; ANALYZE TABLE t1_innodb, t1_myisam, t1_xengine; # Run two queries to see cost estimates when run with default cost constants let query_innodb= SELECT * FROM t1_innodb; let query_myisam= SELECT * FROM t1_myisam; let query_xengine= SELECT * FROM t1_xengine; --echo "Explain with cost estimate against InnoDB" eval EXPLAIN FORMAT=JSON $query_innodb; --echo "Explain with cost estimate against MyISAM" eval EXPLAIN FORMAT=JSON $query_myisam; --echo "Explain with cost estimate against XEngine" eval EXPLAIN FORMAT=JSON $query_xengine; # # Update one cost constant in the server cost table and the two cost # constants in the engine cost table (the reason for updating both is that # after a restart the statistics about whether pages are in memory or on disk # may vary). The new value is double of the default value. # UPDATE mysql.server_cost SET cost_value=0.4 WHERE cost_name="row_evaluate_cost"; UPDATE mysql.engine_cost SET cost_value=2.0 WHERE cost_name="memory_block_read_cost"; UPDATE mysql.engine_cost SET cost_value=2.0 WHERE cost_name="io_block_read_cost"; --echo "Restarting MySQL server" --source include/restart_mysqld.inc --echo "MySQL restarted" SELECT cost_name, cost_value FROM mysql.server_cost; SELECT engine_name, cost_name, cost_value FROM mysql.engine_cost; # # Run the two queries an validate that the cost estimate has doubled # --echo "Explain with cost estimate against InnoDB" eval EXPLAIN FORMAT=JSON $query_innodb; --echo "Explain with cost estimate against MyISAM" eval EXPLAIN FORMAT=JSON $query_myisam; --echo "Explain with cost estimate against XEngine" eval EXPLAIN FORMAT=JSON $query_xengine; # Reset the cost constants UPDATE mysql.server_cost SET cost_value=DEFAULT; UPDATE mysql.engine_cost SET cost_value=DEFAULT; # # Test that adding engine specific cost constants does not influence # other engines. # INSERT INTO mysql.engine_cost VALUES ("InnoDB", 0, "memory_block_read_cost", 4.0, CURRENT_TIMESTAMP, DEFAULT, DEFAULT); INSERT INTO mysql.engine_cost VALUES ("InnoDB", 0, "io_block_read_cost", 4.0, CURRENT_TIMESTAMP, DEFAULT, DEFAULT); --echo "Restarting MySQL server" --source include/restart_mysqld.inc --echo "MySQL restarted" SELECT cost_name, cost_value FROM mysql.server_cost; SELECT engine_name, cost_name, cost_value FROM mysql.engine_cost; # # Run the two queries and validate that the query against MyISAM has # the original cost estimates while the read cost for InnoDB should # be four times the original # --echo "Explain with cost estimate against InnoDB" eval EXPLAIN FORMAT=JSON $query_innodb; --echo "Explain with cost estimate against MyISAM" eval EXPLAIN FORMAT=JSON $query_myisam; --echo "Explain with cost estimate against XEngine" eval EXPLAIN FORMAT=JSON $query_xengine; # Delete the added entry for InnoDB DELETE FROM mysql.engine_cost WHERE engine_name NOT LIKE "default"; --echo "Restarting MySQL server" --source include/restart_mysqld.inc DROP TABLE t0, t1_innodb, t1_myisam, t1_xengine; --source suite/xengine/include/check_xengine_log_error.inc