a long semaphore wait
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
Percona Server moved to https://jira.percona.com/projects/PS |
Fix Released
|
Critical
|
Unassigned | ||
5.1 |
Invalid
|
Undecided
|
Unassigned | ||
5.5 |
Fix Released
|
Critical
|
Unassigned |
Bug Description
My Percona server crashed for the second time in two weeks.
I am not sure what the issue is, but the server becomes unresponsive and I cannot connect to it.
Here is the error log out put:
-lock on RW-latch at 0x2977a48 '&buf_pool-
a writer (thread id 140389372684032) has reserved it in mode wait exclusive
number of readers 1, waiters flag 1, lock_word: ffffffffffffffff
Last time read locked in file buf0buf.c line 2529
Last time write locked in file /home/jenkins/
InnoDB: Warning: a long semaphore wait:
--Thread 140389378275072 has waited at dict0dict.c line 744 for 252.00 seconds the semaphore:
Mutex at 0x3da81288 '&dict_sys->mutex', lock var 1
waiters flag 1
InnoDB: Warning: a long semaphore wait:
--Thread 140389352183552 has waited at buf0buf.c line 2529 for 246.00 seconds the semaphore:
S-lock on RW-latch at 0x2977a48 '&buf_pool-
a writer (thread id 140389372684032) has reserved it in mode wait exclusive
number of readers 1, waiters flag 1, lock_word: ffffffffffffffff
Last time read locked in file buf0buf.c line 2529
Last time write locked in file /home/jenkins/
InnoDB: Warning: a long semaphore wait:
--Thread 140389349787392 has waited at dict0dict.c line 744 for 241.00 seconds the semaphore:
Mutex at 0x3da81288 '&dict_sys->mutex', lock var 1
waiters flag 1
InnoDB: ###### Starts InnoDB Monitor for 30 secs to print diagnostic info:
InnoDB: Pending preads 0, pwrites 0
InnoDB: ###### Diagnostic info printed to the standard error stream
Looks like a duplicate of https:/ /bugs.launchpad .net/percona- server/ +bug/1007268 which is a bug on page_hash_latch ordering.
The workaround is to enable innodb_ lazy_drop_ table to 1.