Storage engines
InnoDB
Supports transactions, row-level locking, and foreign keys
[
Variables
|
Buffer Pool
|
InnoDB Status
]
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2026-02-28 15:46:21 0x7f8d6debe700 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 34 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 4 srv_active, 0 srv_shutdown, 28 srv_idle
srv_master_thread log flush and writes: 0
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 12
OS WAIT ARRAY INFO: signal count 17
RW-shared spins 2, rounds 2, OS waits 0
RW-excl spins 5, rounds 7, OS waits 0
RW-sx spins 0, rounds 0, OS waits 0
Spin rounds per wait: 1.00 RW-shared, 1.40 RW-excl, 0.00 RW-sx
------------
TRANSACTIONS
------------
Trx id counter 9763
Purge done for trx's n:o < 9763 undo n:o < 0 state: running but idle
History list length 57
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 421720969222760, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 421720969221888, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
--------
FILE I/O
--------
I/O thread 0 state: waiting for completed aio requests (insert buffer thread)
I/O thread 1 state: waiting for completed aio requests (log thread)
I/O thread 2 state: waiting for completed aio requests (read thread)
I/O thread 3 state: waiting for completed aio requests (read thread)
I/O thread 4 state: waiting for completed aio requests (read thread)
I/O thread 5 state: waiting for completed aio requests (read thread)
I/O thread 6 state: waiting for completed aio requests (write thread)
I/O thread 7 state: waiting for completed aio requests (write thread)
I/O thread 8 state: waiting for completed aio requests (write thread)
I/O thread 9 state: waiting for completed aio requests (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
1576 OS file reads, 306 OS file writes, 69 OS fsyncs
45.03 reads/s, 19481 avg bytes/read, 8.74 writes/s, 1.97 fsyncs/s
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INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 0, seg size 2, 0 merges
merged operations:
insert 0, delete mark 0, delete 0
discarded operations:
insert 0, delete mark 0, delete 0
Hash table size 34679, node heap has 2 buffer(s)
Hash table size 34679, node heap has 2 buffer(s)
Hash table size 34679, node heap has 1 buffer(s)
Hash table size 34679, node heap has 0 buffer(s)
Hash table size 34679, node heap has 1 buffer(s)
Hash table size 34679, node heap has 3 buffer(s)
Hash table size 34679, node heap has 3 buffer(s)
Hash table size 34679, node heap has 8 buffer(s)
10967.06 hash searches/s, 8540.93 non-hash searches/s
---
LOG
---
Log sequence number 50952827
Log buffer assigned up to 50952827
Log buffer completed up to 50952827
Log written up to 50952827
Log flushed up to 50952827
Added dirty pages up to 50952827
Pages flushed up to 50952827
Last checkpoint at 50952827
42 log i/o's done, 1.24 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 137363456
Dictionary memory allocated 831191
Buffer pool size 8192
Free buffers 6557
Database pages 1615
Old database pages 576
Modified db pages 0
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 39, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1473, created 229, written 183
0.00 reads/s, 0.00 creates/s, 0.00 writes/s
Buffer pool hit rate 1000 / 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: 1615, unzip_LRU len: 0
I/O sum[164]: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=369, Main thread ID=140245486196480 , state=sleeping
Number of rows inserted 9078, updated 324, deleted 0, read 482927
266.99 inserts/s, 9.53 updates/s, 0.00 deletes/s, 14203.32 reads/s
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END OF INNODB MONITOR OUTPUT
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