Hello,everyone:
I faced a very strange phenomenon,
MySQL 8.0.19 is stuck due to the execution of a big transaction,no matter what SQL statement is executed, MySQL does not respond,i am feel confused,it’s a mysql bug? or please tell me the reason,thank you.
the error message is below：
a writer (thread id 140409161828096)has reserved it in mode exclusive
number of readers 0, waiters flag 1, lock word: 0
Last time read locked in file ibufoibuf cc line 4167
Last time write locked in file /./mysql-80 19/storage/innobase/include/mtr0mtr ic line 142
2022-01-08T01: 15: 25. 323195+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait Thread 140405635020544 has waited at trxotrx cc line 530 for 267 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys.cc: 508, lock var 1
2022-01-08T01: 15: 25. 323210+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait -Thread 140404833646336 has waited at trx0trx ce line 622 for 01 seconds the semaphore: Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
2022-01-08T01: 15: 25. 323230+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait -Thread 140405585196800 has waited at trxOtrx cc line 622 for 279 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX_SYS created trxOsys. ce: 508, lock var 1
2022-01-08T01: 15: 25. 323246+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait Thread 140405018912512 has waited at trxotrx cc line 530 for 299 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
2022-01-08T01: 15: 25. 323260+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait Thread 140405012784896 has waited at trxotrx cc line 530 for 279 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
2022-01-08T01: 15: 25. 323275+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait -Thread 140404966344448 has waited at trx0trx cc line 622 for 301 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
2022-01-08T01: 15: 25. 323291-+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait: --Thread 140405020256000 has waited at trx0trx cc line 622 for 279 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
2022-01-08T01: 15: 25. 323306+08: 00 0 [Warning] [MY-012985] [InnoDB] A long semaphore wait Thread 140405016225536 has waited at readoread cc line 549 for 276 seconds the semaphore Mutex at 0x7fb654330128, Mutex TRX SYS created trx0sys. cc: 508, lock var 1
InnoDB: ##### Starts InnoDB Monitor for 30 secs to print diagnostic info:
InnoDB: Pending preads 0, writes 0
InnoDB: ##### Diagnostic info printed to the standard error stream