Description:
hi:
our database is encounter same problems every transaction is hang, version is 5.6.36
in innodb information i find SEMAPHORE rw-lock wait in writer trx0rseg.ic line 46
and reader buf0flu.cc line 1078.
every transaction is in prepered state,session is in query end state.
This is SEMAPHORE info:
----------
SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 708761
--Thread 140059391584000 has waited at trx0rseg.ic line 46 for 274.00 seconds the semaphore:
X-lock (wait_ex) on RW-latch at 0x7f62b99c6aa0 '&block->lock'
a writer (thread id 140059391584000) has reserved it in mode wait exclusive
number of readers 1, waiters flag 0, lock_word: ffffffffffffffff
Last time read locked in file buf0flu.cc line 1078
Last time write locked in file /mnt/workspace/percona-server-5.6-binaries-release/label_exp/centos6-64/percona-server-5.6.36-82.0/storage/innobase/include/trx0rseg.ic line 46
OS WAIT ARRAY INFO: signal count 709495
Mutex spin waits 29554381, rounds 51811565, OS waits 325030
RW-shared spins 557905, rounds 13109338, OS waits 355688
RW-excl spins 129593, rounds 1616089, OS waits 15507
Spin rounds per wait: 1.75 mutex, 23.50 RW-shared, 12.47 RW-excl
------------
TRANSACTIONS
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Trx id counter 15254045741
Purge done for trx's n:o < 15254044071 undo n:o < 0 state: running but idle
History list length 2497
This is bugs?
Thanks!!
How to repeat:
I can't repeat!
