Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

=====================================
2026-06-10 22:39:47 0x9e40 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 2 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 30605 srv_active, 0 srv_shutdown, 1134170 srv_idle
srv_master_thread log flush and writes: 1164749
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 733487
OS WAIT ARRAY INFO: signal count 208977
RW-shared spins 25207, rounds 726297, OS waits 20937
RW-excl spins 6127, rounds 34271, OS waits 283
RW-sx spins 30, rounds 549, OS waits 15
Spin rounds per wait: 28.81 RW-shared, 5.59 RW-excl, 18.30 RW-sx
------------------------
LATEST FOREIGN KEY ERROR
------------------------
2026-05-29 15:49:05 0x7be4 Transaction:
TRANSACTION 10426, ACTIVE 0 sec updating or deleting
mysql tables in use 2, locked 2
8 lock struct(s), heap size 1128, 4 row lock(s), undo log entries 1
MySQL thread id 3272, OS thread handle 31716, query id 44245 localhost 127.0.0.1 root Updating
DELETE FROM `recruitment_applicants` WHERE `recruitment_applicants`.`id` = 1 LIMIT 1
Foreign key constraint fails for table `top1movers`.`recruitment_final_interviews`:
,
  CONSTRAINT `fk_recruitment_final_applicant` FOREIGN KEY (`applicant_id`) REFERENCES `recruitment_applicants` (`id`) ON UPDATE CASCADE
Trying to delete in parent table, in index PRIMARY tuple:
DATA TUPLE: 34 fields;
 0: len 4; hex 80000001; asc     ;;
 1: len 6; hex 0000000028ba; asc     ( ;;
 2: len 7; hex 6b000001810300; asc k      ;;
 3: len 15; hex 4150502d3230323630352d30303031; asc APP-202605-0001;;
 4: len 11; hex 436861726c65732049616e; asc Charles Ian;;
 5: len 5; hex 416c69646f; asc Alido;;
 6: len 8; hex 4c75626f73616e61; asc Lubosana;;
 7: len 0; hex ; asc ;;
 8: len 3; hex 8f9ca7; asc    ;;
 9: len 4; hex 4d616c65; asc Male;;
 10: len 6; hex 53696e676c65; asc Single;;
 11: len 11; hex 3039363832373031393731; asc 09682701971;;
 12: len 25; hex 636861726c65736c75626f73616e6140676d61696c2e636f6d; asc [email protected];;
 13: len 33; hex 54657374696e67206f6e6c7920616464726573732074657374696e67206f6e6c79; asc Testing only address testing only;;
 14: len 4; hex 80000006; asc     ;;
 15: len 1; hex 01; asc  ;;
 16: len 6; hex 800000753000; asc    u0 ;;
 17: len 3; hex 8fd4be; asc    ;;
 18: len 24; hex 5465737420436f6d70616e790d0a546f70314d6f76657273; asc Test Company  Top1Movers;;
 19: len 29; hex 4f7572204c616479204f6620466174696d6120556e6976657273697479; asc Our Lady Of Fatima University;;
 20: len 40; hex 495420486172647761726520616e6420536f6674776172652054726f75626c6573686f6f74696e67; asc IT Hardware and Software Troubleshooting;;
 21: len 21; hex 74657374206365727469666963617465206f6e6c79; asc test certificate only;;
 22: len 26; hex 313132333133323132312c2032332c2030352f32302f32303236; asc 1123132121, 23, 05/20/2026;;
 23: len 19; hex 74657374206f6e6c792074657374206f6e6c79; asc test only test only;;
 24: len 6; hex 496e64656564; asc Indeed;;
 25: len 26; hex 48697265206d6520706c656173652c2049206e656564204a6f62; asc Hire me please, I need Job;;
 26: len 1; hex 03; asc  ;;
 27: len 1; hex 81; asc  ;;
 28: len 5; hex 99b9e8b71c; asc      ;;
 29: len 3; hex 3a3a31; asc ::1;;
 30: len 2; hex 7631; asc v1;;
 31: SQL NULL;
 32: len 5; hex 99b9e8b71c; asc      ;;
 33: len 5; hex 99b9f32c01; asc    , ;;

But in child table `top1movers`.`recruitment_final_interviews`, in index idx_recruitment_final_applicant, there is a record:
PHYSICAL RECORD: n_fields 2; compact format; info bits 0
 0: len 4; hex 80000001; asc     ;;
 1: len 4; hex 80000001; asc     ;;

------------
TRANSACTIONS
------------
Trx id counter 98633
Purge done for trx's n:o < 98633 undo n:o < 0 state: running but idle
History list length 0
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 284082188898448, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284082188910952, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284082188906784, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284082188902616, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
--------
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
118531 OS file reads, 358740 OS file writes, 221973 OS fsyncs
9.00 reads/s, 16384 avg bytes/read, 22.99 writes/s, 10.99 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 482 merges
merged operations:
 insert 1695, delete mark 0, delete 0
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)
135.43 hash searches/s, 133.43 non-hash searches/s
---
LOG
---
Log sequence number 66368657
Log flushed up to   66368401
Pages flushed up to 66362873
Last checkpoint at  66359890
0 pending log flushes, 0 pending chkp writes
121012 log i/o's done, 6.00 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 448216
Buffer pool size   1003
Free buffers       730
Database pages     265
Old database pages 0
Modified db pages  11
Percent of dirty pages(LRU & free pages): 1.104
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 296, not young 3373
0.00 youngs/s, 0.00 non-youngs/s
Pages read 118355, created 2574, written 202285
9.00 reads/s, 0.00 creates/s, 14.99 writes/s
Buffer pool hit rate 988 / 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: 265, unzip_LRU len: 0
I/O sum[448]: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=10260, Main thread ID=15756, state: sleeping
Number of rows inserted 5394, updated 39332, deleted 449, read 8991330
0.00 inserts/s, 4.00 updates/s, 0.00 deletes/s, 339.83 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 217155
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================