Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

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2026-08-14 23:16:43 0x16a4 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 44 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 6890 srv_active, 0 srv_shutdown, 13157 srv_idle
srv_master_thread log flush and writes: 20047
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 47960
OS WAIT ARRAY INFO: signal count 11163
RW-shared spins 3202, rounds 91664, OS waits 2931
RW-excl spins 769, rounds 10850, OS waits 287
RW-sx spins 3, rounds 45, OS waits 1
Spin rounds per wait: 28.63 RW-shared, 14.11 RW-excl, 15.00 RW-sx
------------------------
LATEST FOREIGN KEY ERROR
------------------------
2026-08-14 18:52:33 0x29b0 Error in foreign key constraint creation for table `restobar_db`.`#sql-1300_c5`.
A foreign key constraint of name `restobar_db`.`fk_orders_client`
already exists. (Note that internally InnoDB adds 'databasename'
in front of the user-defined constraint name.)
Note that InnoDB's FOREIGN KEY system tables store
constraint names as case-insensitive, with the
MySQL standard latin1_swedish_ci collation. If you
create tables or databases whose names differ only in
the character case, then collisions in constraint
names can occur. Workaround: name your constraints
explicitly with unique names.
------------
TRANSACTIONS
------------
Trx id counter 382390
Purge done for trx's n:o < 382390 undo n:o < 0 state: running
History list length 11
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283441254215968, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254211800, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254207632, 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
69561 OS file reads, 86075 OS file writes, 48794 OS fsyncs
5.52 reads/s, 16384 avg bytes/read, 7.89 writes/s, 4.70 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 746 merges
merged operations:
 insert 700, delete mark 76, delete 30
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 2 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
12.77 hash searches/s, 35.48 non-hash searches/s
---
LOG
---
Log sequence number 88711508
Log flushed up to   88711488
Pages flushed up to 88707257
Last checkpoint at  88700828
0 pending log flushes, 0 pending chkp writes
24095 log i/o's done, 2.48 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 150240
Buffer pool size   1003
Free buffers       732
Database pages     262
Old database pages 0
Modified db pages  10
Percent of dirty pages(LRU & free pages): 1.005
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 16, not young 52
0.00 youngs/s, 0.00 non-youngs/s
Pages read 69500, created 582, written 53563
5.52 reads/s, 0.00 creates/s, 4.61 writes/s
Buffer pool hit rate 956 / 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: 262, unzip_LRU len: 0
I/O sum[533]:cur[1], 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=3820, Main thread ID=5296, state: sleeping
Number of rows inserted 1038, updated 10375, deleted 24, read 8034270
0.00 inserts/s, 1.09 updates/s, 0.00 deletes/s, 47.45 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 22566
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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