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UPDATE performance_schema.setup_instruments SET enabled = 'NO', timed = 'YES';
UPDATE performance_schema.setup_instruments SET enabled = 'YES'
WHERE name LIKE 'wait/io/file/%';
flush status;
DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (id INT PRIMARY KEY, b CHAR(100) DEFAULT 'initial value')
ENGINE=MyISAM;
INSERT INTO t1 (id) VALUES (1), (2), (3), (4), (5), (6), (7), (8);
TRUNCATE TABLE performance_schema.events_waits_history_long;
TRUNCATE TABLE performance_schema.events_waits_history;
TRUNCATE TABLE performance_schema.events_waits_current;
SELECT * FROM t1 WHERE id = 1;
id	b
1	initial value
SET @before_count = (SELECT SUM(TIMER_WAIT)
FROM performance_schema.events_waits_history_long
WHERE (EVENT_NAME = 'wait/io/file/myisam/dfile')
AND (OBJECT_NAME LIKE '%t1.MYD'));
SELECT (@before_count >= 0) as have_before_count;
have_before_count
1
SELECT IF(@before_count > 0, 'Success', 'Failure') has_instrumentation;
has_instrumentation
Success
SELECT * FROM t1 WHERE id < 4;
id	b
1	initial value
2	initial value
3	initial value
SET @after_count = (SELECT SUM(TIMER_WAIT)
FROM performance_schema.events_waits_history_long
WHERE (EVENT_NAME = 'wait/io/file/myisam/dfile')
AND (OBJECT_NAME LIKE '%t1.MYD') AND (1 = 1));
SELECT (@after_count >= 0) as have_after_count;
have_after_count
1
SELECT IF((@after_count - @before_count) > 0, 'Success', 'Failure') test_ff1_timed;
test_ff1_timed
Success
UPDATE performance_schema.setup_instruments SET enabled='NO';
SET @before_count = (SELECT SUM(TIMER_WAIT)
FROM performance_schema.events_waits_history_long
WHERE (EVENT_NAME = 'wait/io/file/myisam/dfile')
AND (OBJECT_NAME LIKE '%t1.MYD') AND (2 = 2));
SELECT (@before_count >= 0) as have_before_count;
have_before_count
1
SELECT * FROM t1 WHERE id < 6;
id	b
1	initial value
2	initial value
3	initial value
4	initial value
5	initial value
SET @after_count = (SELECT SUM(TIMER_WAIT)
FROM performance_schema.events_waits_history_long
WHERE (EVENT_NAME = 'wait/io/file/myisam/dfile')
AND (OBJECT_NAME LIKE '%t1.MYD') AND (3 = 3));
SELECT (@after_count >= 0) as have_after_count;
have_after_count
1
SELECT IF((COALESCE(@after_count, 0) - COALESCE(@before_count, 0)) = 0, 'Success', 'Failure') test_ff2_timed;
test_ff2_timed
Success
UPDATE performance_schema.setup_instruments SET enabled = 'YES'
WHERE name LIKE 'wait/io/file/%';
UPDATE performance_schema.setup_instruments SET timed = 'NO';
TRUNCATE TABLE performance_schema.events_waits_history_long;
TRUNCATE TABLE performance_schema.events_waits_history;
TRUNCATE TABLE performance_schema.events_waits_current;
SELECT * FROM t1 WHERE id > 4;
id	b
5	initial value
6	initial value
7	initial value
8	initial value
SELECT * FROM performance_schema.events_waits_history_long
WHERE TIMER_WAIT != NULL
OR TIMER_START != NULL
OR TIMER_END != NULL;
THREAD_ID	EVENT_ID	EVENT_NAME	SOURCE	TIMER_START	TIMER_END	TIMER_WAIT	SPINS	OBJECT_SCHEMA	OBJECT_NAME	OBJECT_TYPE	OBJECT_INSTANCE_BEGIN	NESTING_EVENT_ID	OPERATION	NUMBER_OF_BYTES	FLAGS
SELECT * FROM performance_schema.events_waits_history
WHERE TIMER_WAIT != NULL
OR TIMER_START != NULL
OR TIMER_END != NULL;
THREAD_ID	EVENT_ID	EVENT_NAME	SOURCE	TIMER_START	TIMER_END	TIMER_WAIT	SPINS	OBJECT_SCHEMA	OBJECT_NAME	OBJECT_TYPE	OBJECT_INSTANCE_BEGIN	NESTING_EVENT_ID	OPERATION	NUMBER_OF_BYTES	FLAGS
SELECT * FROM performance_schema.events_waits_current
WHERE TIMER_WAIT != NULL
OR TIMER_START != NULL
OR TIMER_END != NULL;
THREAD_ID	EVENT_ID	EVENT_NAME	SOURCE	TIMER_START	TIMER_END	TIMER_WAIT	SPINS	OBJECT_SCHEMA	OBJECT_NAME	OBJECT_TYPE	OBJECT_INSTANCE_BEGIN	NESTING_EVENT_ID	OPERATION	NUMBER_OF_BYTES	FLAGS
UPDATE performance_schema.setup_instruments SET timed = 'YES';
SELECT * FROM t1 WHERE id < 4;
id	b
1	initial value
2	initial value
3	initial value
DROP TABLE t1;
SELECT SUM(COUNT_READ) AS sum_count_read,
SUM(COUNT_WRITE) AS sum_count_write,
SUM(SUM_NUMBER_OF_BYTES_READ) AS sum_num_bytes_read,
SUM(SUM_NUMBER_OF_BYTES_WRITE) AS sum_num_bytes_write
FROM performance_schema.file_summary_by_instance
WHERE FILE_NAME LIKE CONCAT('%', @@tmpdir, '%') ORDER BY NULL;
SELECT EVENT_NAME, COUNT_STAR, AVG_TIMER_WAIT, SUM_TIMER_WAIT
FROM performance_schema.events_waits_summary_global_by_event_name
WHERE COUNT_STAR > 0
ORDER BY SUM_TIMER_WAIT DESC
LIMIT 10;
SELECT h.EVENT_NAME, SUM(h.TIMER_WAIT) TOTAL_WAIT
FROM performance_schema.events_waits_history_long h
INNER JOIN performance_schema.threads p USING (THREAD_ID)
WHERE p.PROCESSLIST_ID = 1
GROUP BY h.EVENT_NAME
HAVING TOTAL_WAIT > 0;
UPDATE performance_schema.setup_instruments SET enabled = 'YES';
show status like "performance_schema%";
Variable_name	Value
Performance_schema_cond_classes_lost	0
Performance_schema_cond_instances_lost	0
Performance_schema_file_classes_lost	0
Performance_schema_file_handles_lost	0
Performance_schema_file_instances_lost	0
Performance_schema_locker_lost	0
Performance_schema_mutex_classes_lost	0
Performance_schema_mutex_instances_lost	0
Performance_schema_rwlock_classes_lost	0
Performance_schema_rwlock_instances_lost	0
Performance_schema_table_handles_lost	0
Performance_schema_table_instances_lost	0
Performance_schema_thread_classes_lost	0
Performance_schema_thread_instances_lost	0