Storage engines

InnoDB

Percona-XtraDB, Supports transactions, row-level locking, and foreign keys

[ Variables | Buffer Pool | InnoDB Status ]

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2026-06-16 17:50:08 7328 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 58 seconds
-----------------
BACKGROUND THREAD
-----------------
srv_master_thread loops: 22152 srv_active, 0 srv_shutdown, 1098145 srv_idle
srv_master_thread log flush and writes: 1120287
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SEMAPHORES
----------
OS WAIT ARRAY INFO: reservation count 118477
OS WAIT ARRAY INFO: signal count 110410
Mutex spin waits 435505, rounds 5462959, OS waits 92110
RW-shared spins 22217, rounds 660948, OS waits 21850
RW-excl spins 8915, rounds 17214, OS waits 306
Spin rounds per wait: 12.54 mutex, 29.75 RW-shared, 1.93 RW-excl
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TRANSACTIONS
------------
Trx id counter 201755724
Purge done for trx's n:o < 189445454 undo n:o < 0 state: running but idle
History list length 1494
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 0, not started
MySQL thread id 11948258, OS thread handle 0x7328, query id 124862268 localhost 127.0.0.1 root init
SHOW ENGINE INNODB STATUS
---TRANSACTION 190346499, not started
MySQL thread id 1, OS thread handle 0x12c4, query id 0 Reading from net
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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 (read thread)
I/O thread 7 state: native aio handle (read thread)
I/O thread 8 state: native aio handle (read thread)
I/O thread 9 state: native aio handle (read thread)
I/O thread 10 state: native aio handle (write thread)
I/O thread 11 state: native aio handle (write thread)
I/O thread 12 state: native aio handle (write thread)
I/O thread 13 state: native aio handle (write thread)
I/O thread 14 state: native aio handle (write thread)
I/O thread 15 state: native aio handle (write thread)
I/O thread 16 state: native aio handle (write thread)
I/O thread 17 state: native aio handle (write thread)
Pending normal aio reads: 0 [0, 0, 0, 0, 0, 0, 0, 0] , aio writes: 0 [0, 0, 0, 0, 0, 0, 0, 0] ,
 ibuf aio reads: 0, log i/o's: 0, sync i/o's: 0
Pending flushes (fsync) log: 0; buffer pool: 0
360882 OS file reads, 88999 OS file writes, 88993 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.34 writes/s, 0.34 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
600.33 hash searches/s, 256.58 non-hash searches/s
---
LOG
---
Log sequence number 121467874498
Log flushed up to   121467874498
Pages flushed up to 121467874498
Last checkpoint at  121467874498
Max checkpoint age    869019772
Checkpoint age target 841862905
Modified age          0
Checkpoint age        0
0 pending log writes, 0 pending chkp writes
47171 log i/o's done, 0.24 log i/o's/second
----------------------
BUFFER POOL AND MEMORY
----------------------
Total memory allocated 5557452800; in additional pool allocated 0
Total memory allocated by read views 101200808
Internal hash tables (constant factor + variable factor)
    Adaptive hash index 101551056 	(84999016 + 16552040)
    Page hash           1329176 (buffer pool 0 only)
    Dictionary cache    33200687 	(21251248 + 11949439)
    File system         5692400 	(812272 + 4880128)
    Lock system         13282696 	(13281976 + 720)
    Recovery system     0 	(0 + 0)
Dictionary memory allocated 11949439
Buffer pool size        327676
Buffer pool size, bytes 5368643584
Free buffers            4099
Database pages          322567
Old database pages      118990
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 164097, not young 416175
0.00 youngs/s, 0.00 non-youngs/s
Pages read 346884, created 0, written 20918
0.00 reads/s, 0.00 creates/s, 0.05 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: 322567, unzip_LRU len: 0
I/O sum[12]:cur[0], unzip sum[0]:cur[0]
----------------------
INDIVIDUAL BUFFER POOL INFO
----------------------
---BUFFER POOL 0
Buffer pool size        81919
Buffer pool size, bytes 1342160896
Free buffers            1025
Database pages          80641
Old database pages      29747
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 40668, not young 141525
0.00 youngs/s, 0.00 non-youngs/s
Pages read 88970, created 0, written 20917
0.00 reads/s, 0.00 creates/s, 0.05 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: 80641, unzip_LRU len: 0
I/O sum[3]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 1
Buffer pool size        81919
Buffer pool size, bytes 1342160896
Free buffers            1025
Database pages          80642
Old database pages      29748
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 41105, not young 90031
0.00 youngs/s, 0.00 non-youngs/s
Pages read 88799, created 0, written 0
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: 80642, unzip_LRU len: 0
I/O sum[3]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 2
Buffer pool size        81919
Buffer pool size, bytes 1342160896
Free buffers            1025
Database pages          80641
Old database pages      29747
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 41714, not young 65523
0.00 youngs/s, 0.00 non-youngs/s
Pages read 85056, created 0, written 0
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: 80641, unzip_LRU len: 0
I/O sum[3]:cur[0], unzip sum[0]:cur[0]
---BUFFER POOL 3
Buffer pool size        81919
Buffer pool size, bytes 1342160896
Free buffers            1024
Database pages          80643
Old database pages      29748
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 40610, not young 119096
0.00 youngs/s, 0.00 non-youngs/s
Pages read 84059, created 0, written 1
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: 80643, unzip_LRU len: 0
I/O sum[3]: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
0 RW transactions active inside InnoDB
0 RO transactions active inside InnoDB
0 out of 1000 descriptors used
Main thread id 9196, state: sleeping
Number of rows inserted 2, updated 0, deleted 0, read 3208611195
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 3225.15 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 83
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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