数据库版本：
mysql> select @@version; +------------+ | @@version | +------------+ | 5.7.26-log | +------------+
事务隔离级别：
mysql> show variables like '%iso%'; +-----------------------+----------------+ | Variable_name | Value | +-----------------------+----------------+ | transaction_isolation | READ-COMMITTED | | tx_isolation | READ-COMMITTED | +-----------------------+----------------+
会话一：关闭自动提交，锁定表中一行数据
mysql> set autocommit=0; Query OK, 0 rows affected (0.00 sec) mysql> select * from sbtest1 where id=1 lock in share mode; +----+------+-------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------+------+-------+-------+-------+-------+-------+-------+--------+--------+------+------+------+ | id | k | c | pad | name | name2 | name5 | name6 | name7 | name8 | name9 | name10 | name11 | c1 | c2 | c3 | +----+------+-------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------+------+-------+-------+-------+-------+-------+-------+--------+--------+------+------+------+ | 1 | 5015 | 68487932199-96439406143-93774651418-41631865787-96406072701-20604855487-25459966574-28203206787-41238978918-19503783441 | 22195207048-70116052123-74140395089-76317954521-98694025897 | aa | bb | a | a | a | a | a | a | a | NULL | NULL | 0 | +----+------+-------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------+------+-------+-------+-------+-------+-------+-------+--------+--------+------+------+------+ 1 row in set (0.00 sec)
会话二：对该表做DDL操作
mysql> set autocommit=0; Query OK, 0 rows affected (0.00 sec) mysql> alter table sbtest1 add cc1 int;
会话三：显示事务在等待数据字典锁，但在innodb的锁信息表中并未给出锁堵塞信息
mysql> show processlist; +-------+-----------------+--------------------+---------------+---------+---------+---------------------------------+---------------------------------+ | Id | User | Host | db | Command | Time | State | Info | +-------+-----------------+--------------------+---------------+---------+---------+---------------------------------+---------------------------------+ | 1 | event_scheduler | localhost | NULL | Daemon | 1549348 | Waiting on empty queue | NULL | | 39327 | root | 10.200.21.13:39600 | canal_manager | Sleep | 884 | | NULL | | 39436 | root | localhost | sysbench_db | Query | 51 | Waiting for table metadata lock | alter table sbtest1 add cc1 int | | 39465 | root | localhost | NULL | Query | 0 | starting | show processlist | | 39506 | root | localhost | sysbench_db | Query | 6 | Waiting for table metadata lock | select * from sbtest1 | | 39511 | root | localhost | sysbench_db | Sleep | 137 | | NULL | +-------+-----------------+--------------------+---------------+---------+---------+---------------------------------+---------------------------------+ 6 rows in set (0.00 sec)
mysql> select * from INNODB_TRX; +-----------------+-----------+---------------------+-----------------------+------------------+------------+---------------------+-----------+---------------------+-------------------+-------------------+------------------+-----------------------+-----------------+-------------------+-------------------------+---------------------+-------------------+------------------------+----------------------------+---------------------------+---------------------------+------------------+----------------------------+ | trx_id | trx_state | trx_started | trx_requested_lock_id | trx_wait_started | trx_weight | trx_mysql_thread_id | trx_query | trx_operation_state | trx_tables_in_use | trx_tables_locked | trx_lock_structs | trx_lock_memory_bytes | trx_rows_locked | trx_rows_modified | trx_concurrency_tickets | trx_isolation_level | trx_unique_checks | trx_foreign_key_checks | trx_last_foreign_key_error | trx_adaptive_hash_latched | trx_adaptive_hash_timeout | trx_is_read_only | trx_autocommit_non_locking | +-----------------+-----------+---------------------+-----------------------+------------------+------------+---------------------+-----------+---------------------+-------------------+-------------------+------------------+-----------------------+-----------------+-------------------+-------------------------+---------------------+-------------------+------------------------+----------------------------+---------------------------+---------------------------+------------------+----------------------------+ | 421422174436976 | RUNNING | 2019-11-15 09:38:10 | NULL | NULL | 2 | 39511 | NULL | NULL | 0 | 1 | 2 | 1136 | 1 | 0 | 0 | READ COMMITTED | 1 | 1 | NULL | 0 | 0 | 0 | 0 | +-----------------+-----------+---------------------+-----------------------+------------------+------------+---------------------+-----------+---------------------+-------------------+-------------------+------------------+-----------------------+-----------------+-------------------+-------------------------+---------------------+-------------------+------------------------+----------------------------+---------------------------+---------------------------+------------------+----------------------------+ 1 row in set (0.00 sec) mysql> select * from INNODB_locks; Empty set, 1 warning (0.00 sec) mysql> select * from INNODB_LOCK_WAITS; Empty set, 1 warning (0.00 sec)
mysql> show engine innodb status G; *************************** 1. row *************************** Type: InnoDB Name: Status: ===================================== 2019-11-15 09:45:19 0x7f47c8d38700 INNODB MONITOR OUTPUT ===================================== Per second averages calculated from the last 11 seconds ----------------- BACKGROUND THREAD ----------------- srv_master_thread loops: 3581 srv_active, 0 srv_shutdown, 1542568 srv_idle srv_master_thread log flush and writes: 1546144 ---------- SEMAPHORES ---------- OS WAIT ARRAY INFO: reservation count 30450 OS WAIT ARRAY INFO: signal count 19118 RW-shared spins 0, rounds 15075, OS waits 6862 RW-excl spins 0, rounds 433241, OS waits 12516 RW-sx spins 1169, rounds 35046, OS waits 873 Spin rounds per wait: 15075.00 RW-shared, 433241.00 RW-excl, 29.98 RW-sx ------------------------ LATEST DETECTED DEADLOCK ------------------------ 2019-11-14 09:55:27 0x7f47c8a20700 *** (1) TRANSACTION: TRANSACTION 8801, ACTIVE 1 sec starting index read mysql tables in use 1, locked 1 LOCK WAIT 4 lock struct(s), heap size 1136, 3 row lock(s), undo log entries 2 MySQL thread id 16018, OS thread handle 139946286548736, query id 99910 10.138.61.12 root updating DELETE FROM sbtest1 WHERE id=4999 *** (1) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space not gap waiting Record lock, heap no 73 PHYSICAL RECORD: n_fields 6; compact format; info bits 0 0: len 4; hex 80001387; asc ;; 1: len 6; hex 00000000225b; asc "[;; 2: len 7; hex 2e000000201fdb; asc . ;; 3: len 4; hex 80001375; asc u;; 4: len 30; hex 36323536333834383835322d34313830333137393631382d383536313634; asc 62563848852-41803179618-856164; (total 120 bytes); 5: len 30; hex 33303032343434313836392d36363935353436363130382d323939353039; asc 30024441869-66955466108-299509; (total 60 bytes); *** (2) TRANSACTION: TRANSACTION 8795, ACTIVE 1 sec starting index read, thread declared inside InnoDB 5000 mysql tables in use 1, locked 1 4 lock struct(s), heap size 1136, 3 row lock(s), undo log entries 2 MySQL thread id 16017, OS thread handle 139946285467392, query id 99920 10.138.61.12 root updating DELETE FROM sbtest1 WHERE id=4979 *** (2) HOLDS THE LOCK(S): RECORD LOCKS space id 57 page no 100 n bits 144 index PRIMARY of table `sysbench_db`.`sbtest1` trx id 8795 lock_mode X locks rec but not gap Record lock, heap no 73 PHYSICAL RECORD: n_fields 6; compact format; info bits 0 0: len 4; hex 80001387; asc ;; 1: len 6; hex 00000000225b; asc "[;; 2: len 7; hex 2e000000201fdb; asc . ;; 3: len 4; hex 80001375; asc u;; 4: len 30; hex 36323536333834383835322d34313830333137393631382d383536313634; asc 62563848852-41803179618-856164; (total 120 bytes); 5: len 30; hex 33303032343434313836392d36363935353436363130382d323939353039; asc 30024441869-66955466108-299509; (total 60 bytes); *** (2) WAITING FOR THIS LOCK TO BE GRANTED: RECORD LOCKS space id 57 page no 100 n bits 144 index PRIMARY of table `sysbench_db`.`sbtest1` trx id 8795 lock_mode X locks rec but not gap waiting Record lock, heap no 53 PHYSICAL RECORD: n_fields 6; compact format; info bits 0 0: len 4; hex 80001373; asc s;; 1: len 6; hex 000000002261; asc "a;; 2: len 7; hex 310000001f2239; asc 1 "9;; 3: len 4; hex 800013aa; asc ;; 4: len 30; hex 31333735393532343036322d37383433393531343532342d383137393338; asc 13759524062-78439514524-817938; (total 120 bytes); 5: len 30; hex 34353737383233343435352d38303336313338353035392d383834323633; asc 45778234455-80361385059-884263; (total 60 bytes); *** WE ROLL BACK TRANSACTION (2) ------------ TRANSACTIONS ------------ Trx id counter 2258851 Purge done for trx's n:o < 2258850 undo n:o < 0 state: running but idle History list length 49 LIST OF TRANSACTIONS FOR EACH SESSION: ---TRANSACTION 421422174438800, not started 0 lock struct(s), heap size 1136, 0 row lock(s) ---TRANSACTION 421422174437888, not started 0 lock struct(s), heap size 1136, 0 row lock(s) ---TRANSACTION 421422174436064, not started 0 lock struct(s), heap size 1136, 0 row lock(s) ---TRANSACTION 421422174435152, not started 0 lock struct(s), heap size 1136, 0 row lock(s) -------- FILE I/O -------- I/O thread 0 state: waiting for completed aio requests (insert buffer thread) I/O thread 1 state: waiting for completed aio requests (log thread) I/O thread 2 state: waiting for completed aio requests (read thread) I/O thread 3 state: waiting for completed aio requests (read thread) I/O thread 4 state: waiting for completed aio requests (read thread) I/O thread 5 state: waiting for completed aio requests (read thread) I/O thread 6 state: waiting for completed aio requests (read thread) I/O thread 7 state: waiting for completed aio requests (read thread) I/O thread 8 state: waiting for completed aio requests (read thread) I/O thread 9 state: waiting for completed aio requests (read thread) I/O thread 10 state: waiting for completed aio requests (write thread) I/O thread 11 state: waiting for completed aio requests (write thread) I/O thread 12 state: waiting for completed aio requests (write thread) I/O thread 13 state: waiting for completed aio requests (write thread) I/O thread 14 state: waiting for completed aio requests (write thread) I/O thread 15 state: waiting for completed aio requests (write thread) I/O thread 16 state: waiting for completed aio requests (write thread) I/O thread 17 state: waiting for completed aio requests (write thread) Pending normal aio reads: [0, 0, 0, 0, 0, 0, 0, 0] , aio writes: [0, 0, 0, 0, 0, 0, 0, 0] , ibuf aio reads:, log i/o's:, sync i/o's: Pending flushes (fsync) log: 0; buffer pool: 0 613084 OS file reads, 1249482 OS file writes, 643052 OS fsyncs 0.00 reads/s, 0 avg bytes/read, 0.00 writes/s, 0.00 fsyncs/s ------------------------------------- INSERT BUFFER AND ADAPTIVE HASH INDEX ------------------------------------- Ibuf: size 1, free list len 126, seg size 128, 20513 merges merged operations: insert 124338, delete mark 486, delete 0 discarded operations: insert 35606, delete mark 359, delete 0 Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 1 buffer(s) Hash table size 34679, node heap has 231 buffer(s) 0.00 hash searches/s, 0.00 non-hash searches/s --- LOG --- Log sequence number 1625718660 Log flushed up to 1625718660 Pages flushed up to 1625718660 Last checkpoint at 1625718651 0 pending log flushes, 0 pending chkp writes 585541 log i/o's done, 0.00 log i/o's/second ---------------------- BUFFER POOL AND MEMORY ---------------------- Total large memory allocated 137428992 Dictionary memory allocated 264434 Buffer pool size 8192 Free buffers 4096 Database pages 3858 Old database pages 1404 Modified db pages 0 Pending reads 0 Pending writes: LRU 0, flush list 0, single page 0 Pages made young 51385, not young 13979456 0.00 youngs/s, 0.00 non-youngs/s Pages read 612973, created 365347, written 614329 0.00 reads/s, 0.00 creates/s, 0.00 writes/s No buffer pool page gets since the last printout Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s LRU len: 3858, unzip_LRU len: 0 I/O sum[0]:cur[0], unzip sum[0]:cur[0] -------------- ROW OPERATIONS -------------- 0 queries inside InnoDB, 0 queries in queue 0 read views open inside InnoDB Process ID=2589, Main thread ID=139946660714240, state: sleeping Number of rows inserted 8673974, updated 7522, deleted 3147, read 45773008 0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s ---------------------------- END OF INNODB MONITOR OUTPUT ============================ 1 row in set (0.09 sec) ERROR: No query specified