Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

=====================================
2026-10-16 04:40:44 0x4a0c INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 41 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 48338 srv_active, 0 srv_shutdown, 24017 srv_idle
srv_master_thread log flush and writes: 72355
----------
SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 1562102
OS WAIT ARRAY INFO: signal count 334033
RW-shared spins 36449, rounds 814271, OS waits 25472
RW-excl spins 12016, rounds 52721, OS waits 963
RW-sx spins 1039, rounds 4526, OS waits 42
Spin rounds per wait: 22.34 RW-shared, 4.39 RW-excl, 4.36 RW-sx
------------
TRANSACTIONS
------------
Trx id counter 7199886
Purge done for trx's n:o < 7199886 undo n:o < 0 state: running but idle
History list length 2
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283173588767008, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283173588762840, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283173588758672, 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
7791 OS file reads, 695425 OS file writes, 454733 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 8.98 writes/s, 6.07 fsyncs/s
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX
-------------------------------------
Ibuf: size 1, free list len 12, seg size 14, 0 merges
merged operations:
 insert 0, delete mark 0, delete 0
discarded operations:
 insert 0, delete mark 0, delete 0
Hash table size 553253, node heap has 16 buffer(s)
Hash table size 553253, node heap has 157 buffer(s)
Hash table size 553253, node heap has 167 buffer(s)
Hash table size 553253, node heap has 15 buffer(s)
Hash table size 553253, node heap has 23 buffer(s)
Hash table size 553253, node heap has 39 buffer(s)
Hash table size 553253, node heap has 52 buffer(s)
Hash table size 553253, node heap has 13 buffer(s)
13.02 hash searches/s, 32.46 non-hash searches/s
---
LOG
---
Log sequence number 5276435706
Log flushed up to   5276435706
Pages flushed up to 5276435706
Last checkpoint at  5276435663
0 pending log flushes, 0 pending chkp writes
184464 log i/o's done, 2.39 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 2181038080
Dictionary memory allocated 160256
Buffer pool size   128432
Free buffers       120066
Database pages     7884
Old database pages 3032
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 119, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 7726, created 158, written 337660
0.00 reads/s, 0.00 creates/s, 4.39 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: 7884, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
----------------------
INDIVIDUAL BUFFER POOL INFO
----------------------
---BUFFER POOL 0
Buffer pool size   16054
Free buffers       15197
Database pages     796
Old database pages 311
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 17, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 781, created 15, written 29516
0.00 reads/s, 0.00 creates/s, 0.17 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: 796, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 1
Buffer pool size   16054
Free buffers       15023
Database pages     972
Old database pages 376
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 24, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 966, created 6, written 40233
0.00 reads/s, 0.00 creates/s, 0.53 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: 972, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 2
Buffer pool size   16054
Free buffers       15031
Database pages     959
Old database pages 352
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 26, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 958, created 1, written 399
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: 959, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 3
Buffer pool size   16054
Free buffers       14939
Database pages     1059
Old database pages 403
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 23, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1056, created 3, written 69391
0.00 reads/s, 0.00 creates/s, 1.25 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: 1059, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 4
Buffer pool size   16054
Free buffers       14960
Database pages     1024
Old database pages 397
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 20, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1021, created 3, written 58850
0.00 reads/s, 0.00 creates/s, 0.61 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: 1024, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 5
Buffer pool size   16054
Free buffers       14989
Database pages     1007
Old database pages 391
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1005, created 2, written 47005
0.00 reads/s, 0.00 creates/s, 0.92 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: 1007, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 6
Buffer pool size   16054
Free buffers       14924
Database pages     1071
Old database pages 415
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1008, created 63, written 45117
0.00 reads/s, 0.00 creates/s, 0.44 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: 1071, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 7
Buffer pool size   16054
Free buffers       15003
Database pages     996
Old database pages 387
Modified db pages  0
Percent of dirty pages(LRU & free pages): 0.000
Max dirty pages percent: 75.000
Pending reads 0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 9, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 931, created 65, written 47149
0.00 reads/s, 0.00 creates/s, 0.47 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: 996, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]
--------------
ROW OPERATIONS
--------------
0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=3568, Main thread ID=5372, state: sleeping
Number of rows inserted 10075, updated 81692, deleted 9207, read 168516018
0.00 inserts/s, 1.00 updates/s, 0.00 deletes/s, 15.32 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 277
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 0.00 reads/s
----------------------------
END OF INNODB MONITOR OUTPUT
============================