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 23:01:55 0x1780 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 28 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 9935 srv_active, 0 srv_shutdown, 10520 srv_idle
srv_master_thread log flush and writes: 20455
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 96902
--Thread 5360 has waited at srv0srv.cc line 900 for 0.00 seconds the semaphore:
Mutex at 00007FF6CA7D0C50, Mutex SRV_SYS created srv0srv.cc:1005, lock var 2

OS WAIT ARRAY INFO: signal count 18645
RW-shared spins 4137, rounds 112984, OS waits 3564
RW-excl spins 880, rounds 12299, OS waits 332
RW-sx spins 3, rounds 90, OS waits 2
Spin rounds per wait: 27.31 RW-shared, 13.98 RW-excl, 30.00 RW-sx
------------------------
LATEST FOREIGN KEY ERROR
------------------------
2026-08-14 17:40:13 0xfd8 Error in foreign key constraint creation for table `restobar_db`.`#sql-12c0_36`.
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.
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TRANSACTIONS
------------
Trx id counter 692744
Purge done for trx's n:o < 692744 undo n:o < 0 state: running
History list length 14
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 284279215763600, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284279215771936, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284279215767768, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 284279215776104, 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
187202 OS file reads, 130442 OS file writes, 72304 OS fsyncs
1.14 reads/s, 16384 avg bytes/read, 4.25 writes/s, 1.75 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 1589 merges
merged operations:
 insert 1421, delete mark 170, 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 0 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)
Hash table size 4441, node heap has 1 buffer(s)
4.50 hash searches/s, 11.86 non-hash searches/s
---
LOG
---
Log sequence number 162500817
Log flushed up to   162500797
Pages flushed up to 162484911
Last checkpoint at  162482576
0 pending log flushes, 0 pending chkp writes
34909 log i/o's done, 1.25 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 150240
Buffer pool size   1003
Free buffers       738
Database pages     259
Old database pages 0
Modified db pages  52
Percent of dirty pages(LRU & free pages): 5.210
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 1257, not young 140420
0.00 youngs/s, 0.00 non-youngs/s
Pages read 187141, created 840, written 82605
1.14 reads/s, 0.04 creates/s, 2.75 writes/s
Buffer pool hit rate 968 / 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: 259, unzip_LRU len: 0
I/O sum[325]: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=4216, Main thread ID=5344, state: sleeping
Number of rows inserted 1537, updated 17200, deleted 43, read 14963583
0.00 inserts/s, 0.86 updates/s, 0.00 deletes/s, 4.50 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 38725
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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