Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

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2025-07-18 16:55:43 0xac4 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 24 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 233349 srv_active, 0 srv_shutdown, 4557745 srv_idle
srv_master_thread log flush and writes: 4791094
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 12976665
OS WAIT ARRAY INFO: signal count 9285249
RW-shared spins 9151662, rounds 243421219, OS waits 7402797
RW-excl spins 5775592, rounds 11357645, OS waits 144269
RW-sx spins 119627, rounds 1314924, OS waits 25588
Spin rounds per wait: 26.60 RW-shared, 1.97 RW-excl, 10.99 RW-sx
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LATEST FOREIGN KEY ERROR
------------------------
2025-07-14 14:56:01 0xd18 Transaction:
TRANSACTION 30624628, ACTIVE 0 sec updating or deleting
mysql tables in use 1, locked 1
4 lock struct(s), heap size 1128, 2 row lock(s), undo log entries 1
MySQL thread id 2170701, OS thread handle 3352, query id 44340784 localhost 127.0.0.1 root Updating
DELETE FROM `sizes` WHERE `sizes`.`id` = 1
Foreign key constraint fails for table `freelumadigital`.`designs`:
,
  CONSTRAINT `designs_ibfk_3` FOREIGN KEY (`size_id`) REFERENCES `sizes` (`id`)
Trying to delete or update in parent table, in index PRIMARY tuple:
DATA TUPLE: 5 fields;
 0: len 4; hex 80000001; asc     ;;
 1: len 6; hex 000001d34b74; asc     Kt;;
 2: len 7; hex 3b000001b10aab; asc ;      ;;
 3: len 18; hex 537175617265202831303234783130323429; asc Square (1024x1024);;
 4: len 9; hex 313032347831303234; asc 1024x1024;;

But in child table `freelumadigital`.`designs`, in index size_id, there is a record:
PHYSICAL RECORD: n_fields 2; compact format; info bits 0
 0: len 4; hex 80000001; asc     ;;
 1: len 4; hex 800000cc; asc     ;;

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TRANSACTIONS
------------
Trx id counter 30628789
Purge done for trx's n:o < 30628789 undo n:o < 0 state: running but idle
History list length 0
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283725376028888, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283725376024720, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
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FILE I/O
--------
I/O thread 0 state: native aio handle (insert buffer thread)
I/O thread 1 state: native aio handle (log thread)
I/O thread 2 state: native aio handle (read thread)
I/O thread 3 state: native aio handle (read thread)
I/O thread 4 state: native aio handle (read thread)
I/O thread 5 state: native aio handle (read thread)
I/O thread 6 state: native aio handle (write thread)
I/O thread 7 state: native aio handle (write thread)
I/O thread 8 state: native aio handle (write thread)
I/O thread 9 state: native aio handle (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
448176234 OS file reads, 10529173 OS file writes, 5833414 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 353, seg size 355, 79021 merges
merged operations:
 insert 741648, delete mark 1325442, delete 92367
discarded operations:
 insert 0, delete mark 0, delete 0
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
0.17 hash searches/s, 0.17 non-hash searches/s
---
LOG
---
Log sequence number 3571164534
Log flushed up to   3571164534
Pages flushed up to 3571164534
Last checkpoint at  3571164525
0 pending log flushes, 0 pending chkp writes
4759115 log i/o's done, 0.00 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 307992
Buffer pool size   1003
Free buffers       610
Database pages     385
Old database pages 0
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 680726340, not young 4055683736
0.00 youngs/s, 0.00 non-youngs/s
Pages read 448176163, created 117901, written 5409049
0.00 reads/s, 0.00 creates/s, 0.00 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: 385, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
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ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=7404, Main thread ID=7916, state: sleeping
Number of rows inserted 3424815, updated 403619, deleted 1913778, read 104556910225
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.21 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 286098
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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