Details
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Bug
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Status: Open (View Workflow)
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Major
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Resolution: Unresolved
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5.5(EOL), 10.0(EOL), 10.1(EOL), 10.2(EOL), 10.3(EOL), 10.4(EOL)
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None
Description
SHOW ENGINE INNODB STATUS output seems to use special thread IDs in some sections of the output. For example, check out this line from the SEMAPHORES section:
--Thread 139981888375552 has waited at lock0lock.cc line 7221 for 0.0000 seconds the semaphore:
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Mutex at 0x7f8859c88068 '&lock_sys->mutex', lock var 0
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Last time reserved by thread 18446744073709551615 in file not yet reserved line 0, waiters flag 0
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wait has ended
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This semaphore is supposedly held by a thread with ID 18446744073709551615. This thread ID is FFFFFFFFFFFFFFFF in hex. No threads with this ID are mentioned anywhere in the TRANSACTIONS section, so it does not appear to be a user thread. I would guess that this is a special identifier for some internal thread. If so, then we should document what thread this is referring to:
https://mariadb.com/kb/en/library/show-engine-innodb-status/
Attachments
Issue Links
- relates to
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MDEV-11703 InnoDB background threads show up in the processlist
- Stalled
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MDEV-17237 thread IDs are printed in different formats in different sections of SHOW ENGINE INNODB STATUS output
- Open
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MDEV-18572 Thread executing DROP TABLE listed twice in SHOW ENGINE INNODB STATUS output
- Open
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MDEV-18698 Show InnoDB's internal background threads in SHOW ENGINE INNODB STATUS
- Open
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MDEV-21566 Lock monitor doesn't print a name for RW-latches
- Closed
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MDEV-22087 Increase buffer size for query in SHOW ENGINE INNODB STATUS output
- Open
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MDEV-18429 Consistent non-locking reads do not appear in TRANSACTIONS section of SHOW ENGINE INNODB STATUS
- Closed
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MDEV-21330 Lock monitor doesn't print a semaphore's last reserved thread in non-debug builds and INFORMATION_SCHEMA.INNODB_SYS_SEMAPHORE_WAITS is totally broken
- Closed
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MDEV-21390 lock_print_info_summary() should work even when trx_sys.mutex is locked
- Closed