Storage engines

InnoDB

Supports transactions, row-level locking, and foreign keys

[ Variables | Buffer Pool | InnoDB Status ]

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2026-03-12 10:27:00 0x7f7250091700 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 1 seconds
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BACKGROUND THREAD
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srv_master_thread loops: 78 srv_active, 0 srv_shutdown, 593 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 536
OS WAIT ARRAY INFO: signal count 494
RW-shared spins 91, rounds 167, OS waits 76
RW-excl spins 253, rounds 1876, OS waits 33
RW-sx spins 3, rounds 61, OS waits 2
Spin rounds per wait: 1.84 RW-shared, 7.42 RW-excl, 20.33 RW-sx
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TRANSACTIONS
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Trx id counter 10621
Purge done for trx's n:o < 10621 undo n:o < 0 state: running but idle
History list length 29
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 421604459694696, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 421604459693824, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
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FILE I/O
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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
1332 OS file reads, 4932 OS file writes, 1777 OS fsyncs
0.00 reads/s, 0 avg bytes/read, 0.00 writes/s, 0.00 fsyncs/s
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INSERT BUFFER AND ADAPTIVE HASH INDEX
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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 2 buffer(s)
Hash table size 34679, node heap has 2 buffer(s)
Hash table size 34679, node heap has 5 buffer(s)
Hash table size 34679, node heap has 4 buffer(s)
Hash table size 34679, node heap has 3 buffer(s)
Hash table size 34679, node heap has 8 buffer(s)
7952.05 hash searches/s, 6875.12 non-hash searches/s
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LOG
---
Log sequence number          52840936
Log buffer assigned up to    52840936
Log buffer completed up to   52840936
Log written up to            52840936
Log flushed up to            52840936
Added dirty pages up to      52840936
Pages flushed up to          52840936
Last checkpoint at           52840936
2303 log i/o's done, 0.00 log i/o's/second
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BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 137363456
Dictionary memory allocated 556764
Buffer pool size   8192
Free buffers       6669
Database pages     1495
Old database pages 531
Modified db pages  0
Pending reads      0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 1026, not young 1545
0.00 youngs/s, 0.00 non-youngs/s
Pages read 1199, created 308, written 2320
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: 1495, unzip_LRU len: 0
I/O sum[187]:cur[0], unzip sum[0]:cur[0]
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ROW OPERATIONS
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0 queries inside InnoDB, 0 queries in queue
0 read views open inside InnoDB
Process ID=368, Main thread ID=140128976815872 , state=sleeping
Number of rows inserted 1100, updated 2541, deleted 1845, read 3214502
0.00 inserts/s, 0.00 updates/s, 0.00 deletes/s, 10220.78 reads/s
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END OF INNODB MONITOR OUTPUT
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