Storage engines

InnoDB

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

[ Variables | Buffer Pool | InnoDB Status ]

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2026-04-05 15:38:03 0xce8 INNODB MONITOR OUTPUT
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Per second averages calculated from the last 29 seconds
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BACKGROUND THREAD
-----------------
srv_master_thread loops: 1377 srv_active, 0 srv_shutdown, 1215503 srv_idle
srv_master_thread log flush and writes: 1216880
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SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 45396
--Thread 6404 has waited at srv0srv.cc line 900 for 0.00 seconds the semaphore:
Mutex at 00007FF7153D0C50, Mutex SRV_SYS created srv0srv.cc:1005, lock var 2

--Thread 3684 has waited at srv0srv.cc line 900 for 0.00 seconds the semaphore:
Mutex at 00007FF7153D0C50, Mutex SRV_SYS created srv0srv.cc:1005, lock var 2

OS WAIT ARRAY INFO: signal count 15307
RW-shared spins 827, rounds 24774, OS waits 420
RW-excl spins 29, rounds 861, OS waits 9
RW-sx spins 0, rounds 0, OS waits 0
Spin rounds per wait: 29.96 RW-shared, 29.69 RW-excl, 0.00 RW-sx
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TRANSACTIONS
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Trx id counter 6099
Purge done for trx's n:o < 6099 undo n:o < 0 state: running
History list length 52
LIST OF TRANSACTIONS FOR EACH SESSION:
---TRANSACTION 283616183246992, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
---TRANSACTION 283616183251160, not started
0 lock struct(s), heap size 1128, 0 row lock(s)
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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 (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
5108 OS file reads, 19127 OS file writes, 9238 OS fsyncs
1.34 reads/s, 16384 avg bytes/read, 6.79 writes/s, 4.31 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 4441, node heap has 1 buffer(s)
Hash table size 4441, node heap has 0 buffer(s)
Hash table size 4441, node heap has 0 buffer(s)
Hash table size 4441, node heap has 0 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 0 buffer(s)
Hash table size 4441, node heap has 1 buffer(s)
9.21 hash searches/s, 19.38 non-hash searches/s
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LOG
---
Log sequence number 4109775
Log flushed up to   4109775
Pages flushed up to 4108609
Last checkpoint at  4103876
0 pending log flushes, 0 pending chkp writes
5179 log i/o's done, 2.45 log i/o's/second
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BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 33554432
Dictionary memory allocated 80128
Buffer pool size   1003
Free buffers       742
Database pages     258
Old database pages 0
Modified db pages  3
Percent of dirty pages(LRU & free pages): 0.300
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 5072, created 321, written 12352
1.34 reads/s, 0.00 creates/s, 3.69 writes/s
Buffer pool hit rate 974 / 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: 258, unzip_LRU len: 0
I/O sum[329]:cur[13], 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=7040, Main thread ID=3472, state: sleeping
Number of rows inserted 1, updated 2940, deleted 0, read 25763
0.00 inserts/s, 1.21 updates/s, 0.00 deletes/s, 9.07 reads/s
Number of system rows inserted 0, updated 0, deleted 0, read 2576
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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