# restart
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');
# Switch to (con1, localhost, user1, , )
connect  con1, localhost, user1, , ;
# Switch to (con2, localhost, user2, , )
connect  con2, localhost, user2, , ;
connection default;
drop function if exists thread_id_name;
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;
//
select thread_id_name(NULL);
thread_id_name(NULL)
NULL
select thread_id_name(@user1_tid);
thread_id_name(@user1_tid)
USER1
select thread_id_name(@user2_tid);
thread_id_name(@user2_tid)
USER2
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\';";
truncate table performance_schema.events_statements_summary_by_digest;
flush global status;
flush tables;
DROP TABLE IF EXISTS t1;
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;
SELECT * from t1 where id=1;
id b
1 initial value
connection default;
"---- Marker 1 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
connection con1;
COMMIT;
connection default;
"---- Marker 2 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
connection con1;
BEGIN;
UPDATE t1 set b="new value" where id=2;
connection default;
"---- Marker 3 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
connection con2;
BEGIN;
DROP TABLE t1;;
connection default;
"---- Marker 4 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE SCHEMA
OBJECT_SCHEMA test
OBJECT_NAME NULL
LOCK_TYPE INTENTION_EXCLUSIVE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE EXCLUSIVE
LOCK_DURATION TRANSACTION
LOCK_STATUS PENDING
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
connection con1;
COMMIT;
connection con2;
connection default;
"---- Marker 5 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
execute dump_table_handles;
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
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;
LOCK TABLE t1 READ;
connection default;
"---- Marker 6 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ NO INSERT
EXTERNAL_LOCK READ EXTERNAL
OWNER_THREAD_ID USER1
execute dump_waits_current;
execute dump_waits_history_long;
connection con2;
LOCK TABLE t1 write;;
connection default;
"---- Marker 7 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE SCHEMA
OBJECT_SCHEMA test
OBJECT_NAME NULL
LOCK_TYPE INTENTION_EXCLUSIVE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_NO_READ_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS PENDING
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ NO INSERT
EXTERNAL_LOCK READ EXTERNAL
OWNER_THREAD_ID USER1
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
connection con1;
UNLOCK TABLES;
connection con2;
connection default;
"---- Marker 8 ----"
execute dump_metadata_locks;
OBJECT_TYPE BACKUP
OBJECT_SCHEMA NULL
OBJECT_NAME NULL
LOCK_TYPE BACKUP_DDL
LOCK_DURATION STATEMENT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE BACKUP
OBJECT_SCHEMA NULL
OBJECT_NAME NULL
LOCK_TYPE BACKUP_DML
LOCK_DURATION STATEMENT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE SCHEMA
OBJECT_SCHEMA test
OBJECT_NAME NULL
LOCK_TYPE INTENTION_EXCLUSIVE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_NO_READ_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE
EXTERNAL_LOCK WRITE EXTERNAL
OWNER_THREAD_ID USER2
execute dump_waits_current;
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
connection con1;
LOCK TABLES t1 read;;
connection default;
"---- Marker 9 ----"
execute dump_metadata_locks;
OBJECT_TYPE BACKUP
OBJECT_SCHEMA NULL
OBJECT_NAME NULL
LOCK_TYPE BACKUP_DDL
LOCK_DURATION STATEMENT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE BACKUP
OBJECT_SCHEMA NULL
OBJECT_NAME NULL
LOCK_TYPE BACKUP_DML
LOCK_DURATION STATEMENT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE SCHEMA
OBJECT_SCHEMA test
OBJECT_NAME NULL
LOCK_TYPE INTENTION_EXCLUSIVE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_NO_READ_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS PENDING
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE
EXTERNAL_LOCK WRITE EXTERNAL
OWNER_THREAD_ID USER2
execute dump_waits_current;
THREAD_ID USER1
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
connection con2;
UNLOCK TABLES;
connection con1;
connection default;
"---- Marker 10 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ NO INSERT
EXTERNAL_LOCK READ EXTERNAL
OWNER_THREAD_ID USER1
execute dump_waits_current;
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
THREAD_ID USER1
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
connection con1;
UNLOCK TABLES;
connection default;
"---- Marker 11 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK READ NO INSERT
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
THREAD_ID USER1
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INDEX_NAME NULL
OPERATION metadata lock
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;
UPDATE LOW_PRIORITY t1 SET a=8;
connection default;
"---- Marker 12 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
LOCK_TYPE SHARED_WRITE
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE LOW PRIORITY
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
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);
GET_LOCK('test', 0)
1
connection default;
"---- Marker 13 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
LOCK_TYPE SHARED_NO_WRITE
LOCK_DURATION EXPLICIT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE LOW PRIORITY
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
execute dump_waits_history_long;
connection con2;
SELECT GET_LOCK('test', 120);;
connection default;
"---- Marker 14 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
LOCK_TYPE SHARED_NO_WRITE
LOCK_DURATION EXPLICIT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
LOCK_TYPE SHARED_NO_WRITE
LOCK_DURATION EXPLICIT
LOCK_STATUS PENDING
OWNER_THREAD_ID USER2
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE LOW PRIORITY
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
connection con1;
SELECT RELEASE_LOCK('test');
RELEASE_LOCK('test')
1
connection con2;
GET_LOCK('test', 120)
1
connection default;
"---- Marker 15 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
LOCK_TYPE SHARED_NO_WRITE
LOCK_DURATION EXPLICIT
LOCK_STATUS GRANTED
OWNER_THREAD_ID USER2
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE LOW PRIORITY
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
INDEX_NAME NULL
OPERATION metadata lock
connection con2;
SELECT RELEASE_LOCK('test');
RELEASE_LOCK('test')
1
connection default;
"---- Marker 16 ----"
execute dump_metadata_locks;
OBJECT_TYPE FUNCTION
OBJECT_SCHEMA test
OBJECT_NAME thread_id_name
LOCK_TYPE SHARED
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
OBJECT_TYPE TABLE
OBJECT_SCHEMA performance_schema
OBJECT_NAME metadata_locks
LOCK_TYPE SHARED_READ
LOCK_DURATION TRANSACTION
LOCK_STATUS GRANTED
OWNER_THREAD_ID OTHER
execute dump_table_handles;
OBJECT_TYPE TABLE
OBJECT_SCHEMA test
OBJECT_NAME t1
INTERNAL_LOCK WRITE LOW PRIORITY
EXTERNAL_LOCK NULL
OWNER_THREAD_ID OTHER
execute dump_waits_current;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
INDEX_NAME NULL
OPERATION metadata lock
execute dump_waits_history_long;
THREAD_ID USER2
EVENT_NAME wait/lock/metadata/sql/mdl
TIMER_START_SET 1
TIMER_END_SET 1
OBJECT_TYPE USER LEVEL LOCK
OBJECT_SCHEMA NULL
OBJECT_NAME test
INDEX_NAME NULL
OPERATION metadata lock
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';
show global status like "performance_schema%";
Variable_name Value
Performance_schema_accounts_lost 0
Performance_schema_cond_classes_lost 0
Performance_schema_cond_instances_lost 0
Performance_schema_digest_lost 0
Performance_schema_file_classes_lost 0
Performance_schema_file_handles_lost 0
Performance_schema_file_instances_lost 0
Performance_schema_hosts_lost 0
Performance_schema_index_stat_lost 0
Performance_schema_locker_lost 0
Performance_schema_memory_classes_lost 0
Performance_schema_metadata_lock_lost 0
Performance_schema_mutex_classes_lost 0
Performance_schema_mutex_instances_lost 0
Performance_schema_nested_statement_lost 0
Performance_schema_prepared_statements_lost 0
Performance_schema_program_lost 0
Performance_schema_rwlock_classes_lost 0
Performance_schema_rwlock_instances_lost 0
Performance_schema_session_connect_attrs_lost 0
Performance_schema_socket_classes_lost 0
Performance_schema_socket_instances_lost 0
Performance_schema_stage_classes_lost 0
Performance_schema_statement_classes_lost 0
Performance_schema_table_handles_lost 0
Performance_schema_table_instances_lost 0
Performance_schema_table_lock_stat_lost 0
Performance_schema_thread_classes_lost 0
Performance_schema_thread_instances_lost 0
Performance_schema_users_lost 0