Peter,

oprofile does not have call stack information, that is what we need there.


On Wed, May 5, 2010 at 10:15 PM, Peter Zaitsev <email address hidden> wrote:
> Vadim,
>
> I sent the oprofile report to Yasufumi separately.
>
>
> On Wed, May 5, 2010 at 7:03 PM, Vadim Tkachenko <email address hidden> wrote:
>
>> Peter,
>>
>> Please provide stacktraces using instructions
>> http://www.percona.com/docs/wiki/howto:debug_lock
>>
>> --
>> innodb_buffer_pool_pages_index performance
>> https://bugs.launchpad.net/bugs/576041
>> You received this bug notification because you are a direct subscriber
>> of the bug.
>>
>> Status in Percona Server with XtraDB: Triaged
>>
>> Bug description:
>> Accerssing innodb_buffer_pool_pages_index  can be very slow under load,
>> it also can cause certain mutexes to be locked for long time causing server
>> stall and potentially server crash (if locks are held more than allowed by
>> Innodb watchdog)
>>
>> ----------
>> SEMAPHORES
>> ----------
>> OS WAIT ARRAY INFO: reservation count 4112, signal count 4016
>> --Thread 1235454272 has waited at buf/buf0lru.c line 2046 for 127.00
>> seconds the semaphore:
>> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
>> waiters flag 1
>> --Thread 1247275328 has waited at buf/buf0lru.c line 698 for 127.00 seconds
>> the semaphore:
>> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
>> waiters flag 1
>> --Thread 1214474560 has waited at buf/buf0flu.c line 1077 for 127.00
>> seconds the semaphore:
>> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
>> waiters flag 1
>> --Thread 1245944128 has waited at row/row0purge.c line 543 for 122.00
>> seconds the semaphore:
>> Mutex at 0x6812220 '&dict_sys->mutex', lock var 1
>> waiters flag 1
>> Mutex spin waits 24624, rounds 144847, OS waits 3454
>> RW-shared spins 813, OS waits 483; RW-excl spins 48, OS waits 154
>> Spin rounds per wait: 5.88 mutex, 22.41 RW-shared, 104.08 RW-excl
>>
>> To unsubscribe from this bug, go to:
>> https://bugs.launchpad.net/percona-server/+bug/576041/+subscribe
>>
>
>
> --
> Peter Zaitsev, CEO, Percona Inc.
> Tel: +1 888 401 3401 ext 501   Skype:  peter_zaitsev
> 24/7 Emergency Line +1 888 401 3401 ext 911
>
> Percona Training Workshops
> http://www.percona.com/training/
>
> --
> innodb_buffer_pool_pages_index performance
> https://bugs.launchpad.net/bugs/576041
> You received this bug notification because you are a member of Percona
> developers, which is the registrant for Percona Server.
>
> Status in Percona Server with XtraDB: Triaged
>
> Bug description:
> Accerssing innodb_buffer_pool_pages_index  can be very slow under load,
> it also can cause certain mutexes to be locked for long time causing server stall and potentially server crash (if locks are held more than allowed by Innodb watchdog)
>
> ----------
> SEMAPHORES
> ----------
> OS WAIT ARRAY INFO: reservation count 4112, signal count 4016
> --Thread 1235454272 has waited at buf/buf0lru.c line 2046 for 127.00 seconds the semaphore:
> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
> waiters flag 1
> --Thread 1247275328 has waited at buf/buf0lru.c line 698 for 127.00 seconds the semaphore:
> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
> waiters flag 1
> --Thread 1214474560 has waited at buf/buf0flu.c line 1077 for 127.00 seconds the semaphore:
> Mutex at 0xde2020 '&buf_pool_mutex', lock var 1
> waiters flag 1
> --Thread 1245944128 has waited at row/row0purge.c line 543 for 122.00 seconds the semaphore:
> Mutex at 0x6812220 '&dict_sys->mutex', lock var 1
> waiters flag 1
> Mutex spin waits 24624, rounds 144847, OS waits 3454
> RW-shared spins 813, OS waits 483; RW-excl spins 48, OS waits 154
> Spin rounds per wait: 5.88 mutex, 22.41 RW-shared, 104.08 RW-excl
>
>
>



-- 
Vadim Tkachenko, CTO, Percona Inc.
Phone +1-888-401-3403,  Skype: vadimtk153
Schedule meeting: http://tungle.me/VadimTkachenko