Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

=====================================
2026-08-14 23:18:37 0x1b74 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 53 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 6972 srv_active, 0 srv_shutdown, 13188 srv_idle
srv_master_thread log flush and writes: 20160
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 52262
OS WAIT ARRAY INFO: signal count 11722
RW-shared spins 3240, rounds 92656, OS waits 2951
RW-excl spins 781, rounds 10958, OS waits 289
RW-sx spins 3, rounds 45, OS waits 1
Spin rounds per wait: 28.60 RW-shared, 14.03 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 382894
Purge done for trx's n:o < 382894 undo n:o < 0 state: running
History list length 16
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283441254236808, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254215968, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254245144, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254240976, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254228472, 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)
---TRANSACTION 283441254220136, 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 283441254232640, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283441254224304, 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
71369 OS file reads, 87493 OS file writes, 49491 OS fsyncs
20.94 reads/s, 16384 avg bytes/read, 16.77 writes/s, 8.34 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 756 merges
merged operations:
 insert 708, delete mark 78, 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 1 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
16.87 hash searches/s, 64.87 non-hash searches/s
---
LOG
---
Log sequence number 88984288
Log flushed up to   88984268
Pages flushed up to 88973656
Last checkpoint at  88953232
0 pending log flushes, 0 pending chkp writes
24456 log i/o's done, 4.45 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 150240
Buffer pool size   1003
Free buffers       735
Database pages     260
Old database pages 0
Modified db pages  20
Percent of dirty pages(LRU & free pages): 2.008
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 71308, created 593, written 54494
20.94 reads/s, 0.08 creates/s, 10.77 writes/s
Buffer pool hit rate 988 / 1000, young-making rate 0 / 1000 not 0 / 1000
Pages read ahead 1.79/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 260, unzip_LRU len: 0
I/O sum[1515]:cur[10], unzip sum[0]:cur[0]
--------------
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 1043, updated 10619, deleted 24, read 8305621
0.04 inserts/s, 3.17 updates/s, 0.00 deletes/s, 4019.83 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 23035
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 1.81 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================