config root man

--source include/not_embedded.inc
--source include/have_perfschema.inc

UPDATE performance_schema.setup_instruments SET enabled = 'NO', timed = 'YES';

UPDATE performance_schema.setup_instruments SET enabled = 'YES'
WHERE name in ('wait/io/table/sql/handler',
               'wait/lock/table/sql/handler',
               'wait/lock/metadata/sql/mdl');

set @orig_sql_mode= @@sql_mode;
set sql_mode= (select replace(@@sql_mode,'NO_AUTO_CREATE_USER',''));
grant ALL on *.* to user1@localhost;
grant ALL on *.* to user2@localhost;
set sql_mode= @orig_sql_mode;

insert into performance_schema.setup_objects (object_type, object_schema, object_name, enabled, timed)
  values ('TABLE', 'mtr', '%', 'NO', 'NO');

--echo # Switch to (con1, localhost, user1, , )
connect (con1, localhost, user1, , );

let $user1_tid=`select THREAD_ID from performance_schema.threads where PROCESSLIST_ID=connection_id()`;

--echo # Switch to (con2, localhost, user2, , )
connect (con2, localhost, user2, , );

let $user2_tid=`select THREAD_ID from performance_schema.threads where PROCESSLIST_ID=connection_id()`;

--connection default

--disable_query_log
--eval set @user1_tid= $user1_tid;
--eval set @user2_tid= $user2_tid;
--enable_query_log

--disable_warnings
drop function if exists thread_id_name;
--enable_warnings

--delimiter //

create function thread_id_name(THREAD_ID int)
returns varchar(16)
begin
  if (THREAD_ID IS NULL)
  then
    return NULL;
  end if;
  if (THREAD_ID = @user1_tid)
  then
    return "USER1";
  end if;
  if (THREAD_ID = @user2_tid)
  then
    return "USER2";
  end if;
  return "OTHER";
end;
//

delimiter ;//

select thread_id_name(NULL);
select thread_id_name(@user1_tid);
select thread_id_name(@user2_tid);

prepare dump_metadata_locks from
  "select OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME,
    LOCK_TYPE, LOCK_DURATION, LOCK_STATUS,
    thread_id_name(OWNER_THREAD_ID) as OWNER_THREAD_ID
    from performance_schema.metadata_locks
    order by OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME,
    LOCK_TYPE, LOCK_DURATION, LOCK_STATUS, OWNER_THREAD_ID;";

prepare dump_table_handles from
  "select OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME,
    INTERNAL_LOCK, EXTERNAL_LOCK,
    thread_id_name(OWNER_THREAD_ID) as OWNER_THREAD_ID
    from performance_schema.table_handles
    order by OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME,
    INTERNAL_LOCK, EXTERNAL_LOCK, OWNER_THREAD_ID;";

prepare dump_waits_current from
  "select thread_id_name(THREAD_ID) as THREAD_ID,
    EVENT_NAME,
    TIMER_START is not NULL as TIMER_START_SET,
    TIMER_END is not NULL as TIMER_END_SET,
    OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, INDEX_NAME,
    OPERATION
    from performance_schema.events_waits_current
    where event_name = \'wait/lock/metadata/sql/mdl\';";

prepare dump_waits_history_long from
  "select thread_id_name(THREAD_ID) as THREAD_ID,
    EVENT_NAME,
    TIMER_START is not NULL as TIMER_START_SET,
    TIMER_END is not NULL as TIMER_END_SET,
    OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, INDEX_NAME,
    OPERATION
    from performance_schema.events_waits_history_long
    where event_name = \'wait/lock/metadata/sql/mdl\';";

# reset lost counters
truncate table performance_schema.events_statements_summary_by_digest;
flush status;

flush tables;

--disable_warnings
DROP TABLE IF EXISTS t1;
--enable_warnings

CREATE TABLE t1 (id INT PRIMARY KEY, b CHAR(100) DEFAULT 'initial value');

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;

--connection con1

BEGIN;

# MDL lock granted immediately, no wait.
SELECT * from t1 where id=1;

--connection default

echo "---- Marker 1 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

# The MDL lock is now released
COMMIT;

--connection default

echo "---- Marker 2 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

BEGIN;

# MDL lock is granted immediately, no wait
UPDATE t1 set b="new value" where id=2;

--connection default

echo "---- Marker 3 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con2

BEGIN;

# MDL lock is PENDING : waiting for the update transaction
--send DROP TABLE t1;

--connection default

# Wait for the DROP TABLE t1 to block
let $wait_condition=
  select count(*) = 1 from performance_schema.events_waits_current
  where event_name = 'wait/lock/metadata/sql/mdl'
  and object_name = 't1';
--source include/wait_condition.inc

echo "---- Marker 4 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

# MDL lock on the update is released,
# MDL pending lock is granted for the drop table, then released.
COMMIT;

--connection con2

# complete DROP TABLE t1
--reap

--connection default

echo "---- Marker 5 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection default

TRUNCATE TABLE performance_schema.events_waits_history_long;
TRUNCATE TABLE performance_schema.events_waits_history;
TRUNCATE TABLE performance_schema.events_waits_current;
create table t1 (a int);

--connection con1

# Get MDL read lock
LOCK TABLE t1 READ;

--connection default

echo "---- Marker 6 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con2

# User1 has a READ LOCK
# User2 waiting for WRITE LOCK
--send LOCK TABLE t1 write;

--connection default

# Wait for the LOCK TABLE t1 write to block
let $wait_condition=
  select count(*) = 1 from performance_schema.events_waits_current
  where event_name = 'wait/lock/metadata/sql/mdl'
  and object_name = 't1';
--source include/wait_condition.inc

echo "---- Marker 7 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

# User1 releases a READ LOCK
# User2 granted a WRITE LOCK
UNLOCK TABLES;

--connection con2

# Complete LOCK TABLE t1 write
--reap

--connection default

echo "---- Marker 8 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

# User2 granted a WRITE LOCK
# User1 waits for a READ LOCK
--send LOCK TABLES t1 read;

--connection default

# Wait for the LOCK TABLES t1 READ to block
let $wait_condition=
  select count(*) = 1 from performance_schema.events_waits_current
  where event_name = 'wait/lock/metadata/sql/mdl'
  and object_name = 't1';
--source include/wait_condition.inc

echo "---- Marker 9 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con2

UNLOCK TABLES;

--connection con1

# Complete LOCK TABLE t1 read
--reap

--connection default

echo "---- Marker 10 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

UNLOCK TABLES;

--connection default

echo "---- Marker 11 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results


TRUNCATE TABLE performance_schema.events_waits_history_long;
TRUNCATE TABLE performance_schema.events_waits_history;
TRUNCATE TABLE performance_schema.events_waits_current;
--connection con1

BEGIN;

# MDL lock is granted immediately, no wait
UPDATE LOW_PRIORITY t1 SET a=8;

--connection default

echo "---- Marker 12 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1
COMMIT;

--connection default

TRUNCATE TABLE performance_schema.events_waits_history_long;
TRUNCATE TABLE performance_schema.events_waits_history;
TRUNCATE TABLE performance_schema.events_waits_current;

--connection con1

SELECT GET_LOCK('test', 0);

--connection default

echo "---- Marker 13 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con2

--send SELECT GET_LOCK('test', 120);

--connection default

let $wait_condition=
  select count(*) = 1 from performance_schema.events_waits_current
  where event_name = 'wait/lock/metadata/sql/mdl'
  and object_name = 'test';
--source include/wait_condition.inc

echo "---- Marker 14 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con1

SELECT RELEASE_LOCK('test');

--connection con2

--reap

--connection default

echo "---- Marker 15 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

--connection con2

SELECT RELEASE_LOCK('test');

--connection default

echo "---- Marker 16 ----";

--vertical_results
execute dump_metadata_locks;
execute dump_table_handles;
execute dump_waits_current;
execute dump_waits_history_long;
--horizontal_results

# Cleanup

--disconnect con1
--disconnect con2

--connection default

drop table t1;

UPDATE performance_schema.setup_instruments SET enabled = 'YES', timed = 'YES';

revoke all privileges, grant option from user1@localhost;
revoke all privileges, grant option from user2@localhost;

drop user user1@localhost;
drop user user2@localhost;

drop function thread_id_name;

drop prepare dump_metadata_locks;
drop prepare dump_table_handles;
drop prepare dump_waits_current;
drop prepare dump_waits_history_long;

delete from performance_schema.setup_objects
  where object_schema='mtr';

# In case of failure, will indicate the root cause
show global status like "performance_schema%";