Storage engines
InnoDB
Supports transactions, row-level locking, foreign keys and encryption for tables
[
Variables
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Buffer Pool
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InnoDB Status
]
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2026-06-04 22:55:37 0x2300 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 24 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 705705 srv_active, 0 srv_shutdown, 82968 srv_idle
srv_master_thread log flush and writes: 788673
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 66100797
OS WAIT ARRAY INFO: signal count 6330473
RW-shared spins 207212, rounds 5860146, OS waits 109964
RW-excl spins 22133, rounds 696781, OS waits 13483
RW-sx spins 135, rounds 3990, OS waits 83
Spin rounds per wait: 28.28 RW-shared, 31.48 RW-excl, 29.56 RW-sx
------------------------
LATEST FOREIGN KEY ERROR
------------------------
2026-06-01 09:10:37 0x3928 Transaction:
TRANSACTION 10888269, ACTIVE 0 sec inserting
mysql tables in use 1, locked 1
3 lock struct(s), heap size 1128, 1 row lock(s), undo log entries 1
MySQL thread id 2723868, OS thread handle 14632, query id 303829065 localhost 127.0.0.1 root Update
INSERT INTO `payroll_details` VALUES ('payroll_details_id', 'payroll_calendar_id', 'EmployeeId', 'Basic', 'DA', 'HRA', 'Special', 'SignonBonus', 'TA', 'PT', 'TDS', 'PTOUsed', 'PTORemaining', 'LeaveWithoutPay')
Foreign key constraint fails for table `marketing_ops`.`payroll_details`:
,
CONSTRAINT `fk_payroll_employeelist` FOREIGN KEY (`EmployeeId`) REFERENCES `employeelist` (`id`) in parent table, in index fk_payroll_employeelist tuple:
DATA TUPLE: 2 fields;
0: len 4; hex 80000000; asc ;;
1: len 4; hex 80000049; asc I;;
But in parent table `marketing_ops`.`employeelist`, in index PRIMARY,
the closest match we can find is record:
PHYSICAL RECORD: n_fields 15; compact format; info bits 0
0: len 4; hex 80000001; asc ;;
1: len 6; hex 000000000000; asc ;;
2: len 7; hex 80000000000000; asc ;;
3: len 4; hex 48433031; asc HC01;;
4: len 6; hex 536f6c616967; asc Solaig;;
5: len 5; hex 536f6c6169; asc Solai;;
6: len 1; hex 47; asc G;;
7: len 10; hex 39383734353633323130; asc 9874563210;;
8: len 4; hex 31303031; asc 1001;;
9: len 10; hex 70617373776f72643032; asc password02;;
10: len 1; hex 30; asc 0;;
11: len 1; hex 34; asc 4;;
12: len 3; hex 8fcb1f; asc ;;
13: len 6; hex 536565746861; asc Seetha;;
14: len 27; hex 736f6c616967406b61696e6f73696e6e6f7661746976652e636f6d; asc solaig@kainosinnovative.com;;
------------
TRANSACTIONS
------------
Trx id counter 12481608
Purge done for trx's n:o < 12481608 undo n:o < 0 state: running
History list length 28
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283852003881824, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003877656, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003865152, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003860984, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003856816, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003844312, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003873488, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003869320, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003840144, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003852648, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283852003848480, 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
27501336 OS file reads, 10463918 OS file writes, 5875327 OS fsyncs
53.41 reads/s, 16384 avg bytes/read, 16.96 writes/s, 9.33 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 16, seg size 18, 4 merges
merged operations:
insert 0, delete mark 4, 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 2 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 0 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
249.74 hash searches/s, 124.16 non-hash searches/s
---
LOG
---
Log sequence number 8428318567
Log flushed up to 8428318547
Pages flushed up to 8428289142
Last checkpoint at 8428288058
0 pending log flushes, 0 pending chkp writes
2931868 log i/o's done, 5.29 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 671072
Buffer pool size 1003
Free buffers 743
Database pages 252
Old database pages 0
Modified db pages 37
Percent of dirty pages(LRU & free pages): 3.715
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 30835, not young 1884960
0.00 youngs/s, 0.00 non-youngs/s
Pages read 27500983, created 100661, written 6210130
53.41 reads/s, 0.37 creates/s, 9.83 writes/s
Buffer pool hit rate 983 / 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: 252, unzip_LRU len: 0
I/O sum[2777]:cur[80], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=10408, Main thread ID=17812, state: sleeping
Number of rows inserted 216, updated 1909553, deleted 86, read 11002142195
0.00 inserts/s, 4.21 updates/s, 0.00 deletes/s, 20518.94 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 162187
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================
