存储引擎

InnoDB

Supports transactions, row-level locking, foreign keys and encryption for tables

[ 变量 | 缓冲池 | InnoDB 状态 ]

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2026-01-22 10:59:16 0x7fe0f4915700 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 11 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 4927 srv_active, 0 srv_shutdown, 3847 srv_idle
srv_master_thread log flush and writes: 8774
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 15883
OS WAIT ARRAY INFO: signal count 13420
RW-shared spins 0, rounds 6301, OS waits 3123
RW-excl spins 0, rounds 1835, OS waits 62
RW-sx spins 0, rounds 0, OS waits 0
Spin rounds per wait: 6301.00 RW-shared, 1835.00 RW-excl, 0.00 RW-sx
------------------------
LATEST FOREIGN KEY ERROR
------------------------
2026-01-22 10:33:23 0x7fe0f48e3700 Transaction:
TRANSACTION 57094, ACTIVE 0 sec inserting
mysql tables in use 1, locked 1
5 lock struct(s), heap size 1136, 2 row lock(s), undo log entries 1
MySQL thread id 81111, OS thread handle 140604152362752, query id 2903623 192.168.30.20 root Update
INSERT INTO `borrow` (`borrow_id`, `book_id`, `reader_id`, `borrow_date`, `return_date`) VALUES
(1, 1, 1, '2024-01-10', '2024-01-20'),
(2, 2, 2, '2024-01-12', '2024-01-25'),
(3, 3, 3, '2024-01-15', '2024-01-30'),
(4, 4, 4, '2024-02-01', '2024-02-15'),
(5, 5, 5, '2024-02-05', '2024-02-20'),
(6, 6, 1, '2024-02-10', '2024-02-22'),
(7, 7, 2, '2024-02-12', '2024-02-28'),
(8, 8, 3, '2024-03-01', '2024-03-15'),
(9, 9, 4, '2024-03-05', '2024-03-20'),
(10, 10, 5, '2024-03-10', '2024-03-25'),
(11, 11, 6, '2024-03-15', '2024-03-30'),
(12, 12, 7, '2024-04-01', '2024-04-15'),
(13, 13, 8, '2024
Foreign key constraint fails for table `Library`.`borrow`:
,
  CONSTRAINT `borrow_ibfk_2` FOREIGN KEY (`reader_id`) REFERENCES `readers` (`reader_id`) in parent table, in index reader_id tuple:
DATA TUPLE: 2 fields;
 0: len 4; hex 80000001; asc     ;;
 1: len 4; hex 80000001; asc     ;;

But in parent table `Library`.`readers`, in index PRIMARY,
the closest match we can find is record:
PHYSICAL RECORD: n_fields 1; compact format; info bits 0
 0: len 8; hex 696e66696d756d00; asc infimum ;;

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TRANSACTIONS
------------
Trx id counter 60856
Purge done for trx's n:o < 60856 undo n:o < 0 state: running but idle
History list length 4
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 422079135039992, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422079135035736, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422079135031480, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
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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 (write thread)
I/O thread 7 state: waiting for completed aio requests (write thread)
I/O thread 8 state: waiting for completed aio requests (write thread)
I/O thread 9 state: waiting for completed aio requests (write thread)
Pending normal aio reads: [0, 0, 0, 0] , aio writes: [0, 0, 0, 0] ,
 ibuf aio reads:, log i/o's:, sync i/o's:
Pending flushes (fsync) log: 0; buffer pool: 0
864 OS file reads, 74053 OS file writes, 36472 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 7.18 writes/s, 2.27 fsyncs/s
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INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 0 merges
merged operations:
 insert 0, delete mark 0, delete 0
discarded operations:
 insert 0, delete mark 0, delete 0
Hash table size 69257, node heap has 1 buffer(s)
Hash table size 69257, node heap has 9 buffer(s)
Hash table size 69257, node heap has 2 buffer(s)
Hash table size 69257, node heap has 25 buffer(s)
Hash table size 69257, node heap has 1 buffer(s)
Hash table size 69257, node heap has 3 buffer(s)
Hash table size 69257, node heap has 25 buffer(s)
Hash table size 69257, node heap has 0 buffer(s)
2.36 hash searches/s, 0.00 non-hash searches/s
---
LOG
---
Log sequence number 24526801
Log flushed up to   24526651
Pages flushed up to 24524201
Last checkpoint at  24524158
0 pending log flushes, 0 pending chkp writes
22615 log i/o's done, 1.27 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 285212672
Dictionary memory allocated 136272
Buffer pool size   16024
Free buffers       15093
Database pages     865
Old database pages 330
Modified db pages  5
Percent of dirty pages(LRU & free pages): 0.031
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 705, created 160, written 46155
0.00 reads/s, 0.00 creates/s, 5.54 writes/s
Buffer pool hit rate 1000 / 1000, young-making rate 0 / 1000 not 0 / 1000
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 865, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
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ROW OPERATIONS
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0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=910, Main thread ID=140603388057344, state: sleeping
Number of rows inserted 40, updated 11230, deleted 1, read 1094324
0.00 inserts/s, 0.55 updates/s, 0.00 deletes/s, 1.09 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 3571
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
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END OF INNODB MONITOR OUTPUT
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