Hello,  seems deadlock happens when heat craates network objects.
I am not sure, but if I remember some db deadlock also in cinder.
Any case with the workaround heat never fails for db deadlock and Now stack deleting do not stop.
Ignazio

Il giorno Mar 18 Dic 2018 17:06 Mike Bayer <mike_mp@zzzcomputing.com> ha scritto:
On Tue, Dec 18, 2018 at 12:36 AM Ignazio Cassano
<ignaziocassano@gmail.com> wrote:
>
> Yes, I  tried on yesterday and this workaround solved.
> Thanks
> Ignazio

OK, so that means this "deadlock" is not really a deadlock but it is a
write-conflict between two Galera masters.      I have a long term
goal to being relaxing this common requirement that Openstack apps
only refer to one Galera master at a time.    If this is a particular
hotspot for Heat (no pun intended) can we pursue adding a transaction
retry decorator for this operation?  This is the standard approach for
other applications that are subject to galera multi-master writeset
conflicts such as Neutron.




>
> Il giorno Lun 17 Dic 2018 20:38 Joe Topjian <joe@topjian.net> ha scritto:
>>
>> Hi Ignazio,
>>
>> Do you currently have HAProxy configured to route requests to multiple MariaDB nodes? If so, as a workaround, try doing an active/backup configuration where all but 1 node is configured as an HAProxy "backup".
>>
>> Thanks,
>> Joe
>>
>>
>>
>> On Sun, Dec 16, 2018 at 10:46 PM Ignazio Cassano <ignaziocassano@gmail.com> wrote:
>>>
>>> Hello Zane, it happens also when I create a magnum cluster .
>>> My mariadb cluster is behind haproxy.
>>> Do you need any other info?
>>> Thanks
>>> Ignazio
>>>
>>>
>>> Il giorno Lun 17 Dic 2018 00:28 Zane Bitter <zbitter@redhat.com> ha scritto:
>>>>
>>>> On 14/12/18 4:06 AM, Ignazio Cassano wrote:
>>>> > Hi All,
>>>> > I installed queens on centos 7.
>>>> > Heat seems to work fine with templates I wrote but when I create magnum
>>>> > cluster
>>>> > I often face with db deadlock in heat-engine log:
>>>>
>>>> The stacktrace below is in stack delete, so do you mean that the problem
>>>> occurs when deleting a Magnum cluster, or can it occur any time with a
>>>> magnum cluster?
>>>>
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource Traceback (most
>>>> > recent call last):
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/resource.py", line 918, in
>>>> > _action_recorder
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     yield
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/resource.py", line 2035,
>>>> > in delete
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     *action_args)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/scheduler.py", line 346,
>>>> > in wrapper
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     step =
>>>> > next(subtask)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/resource.py", line 977, in
>>>> > action_handler_task
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     done =
>>>> > check(handler_data)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/resources/stack_resource.py",
>>>> > line 587, in check_delete_complete
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     return
>>>> > self._check_status_complete(self.DELETE)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource   File
>>>> > "/usr/lib/python2.7/site-packages/heat/engine/resources/stack_resource.py",
>>>> > line 454, in _check_status_complete
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource     action=action)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource
>>>> > ResourceFailure: resources[0]: (pymysql.err.InternalError) (1213,
>>>> > u'Deadlock found when trying to get lock; try restarting transaction')
>>>> > (Background on this error at: http://sqlalche.me/e/2j85)
>>>> > 2018-12-13 11:48:46.016 89597 ERROR heat.engine.resource
>>>> > 2018-12-13 11:48:46.030 89597 INFO heat.engine.stack
>>>> > [req-9a43184f-77d8-4fad-ab9e-2b9826c10b70 - admin - default default]
>>>> > Stack DELETE FAILED
>>>> > (swarm-clustergp27-ebhsalhb4bop-swarm_primary_master-tzgkh3ncmymw):
>>>> > Resource DELETE failed: resources[0]: (pymysql.err.InternalError) (1213,
>>>> > u'Deadlock found when trying to get lock; try restarting transaction')
>>>> > (Background on this error at: http://sqlalche.me/e/2j85)
>>>> > 2018-12-13 11:48:46.844 89595 INFO heat.engine.resource
>>>> > [req-9a43184f-77d8-4fad-ab9e-2b9826c10b70 - admin - default default]
>>>> > DELETE: ResourceGroup "swarm_primary_master"
>>>> > [6984db3c-3ac1-4afc-901f-21b3e7f230a7] Stack
>>>> > "swarm-clustergp27-ebhsalhb4bop" [b43256fa-52e2-4613-ac15-63fd9340a8be]
>>>> >
>>>> >
>>>> > I read this issue was solved in heat version 10 but seems not.
>>>>
>>>> The patch for bug 1732969, which is in Queens, is probably the fix
>>>> you're referring to: https://review.openstack.org/#/c/521170/1
>>>>
>>>> The traceback in that bug included the SQL statement that was failing.
>>>> I'm not sure if that isn't included in your traceback because SQLAlchemy
>>>> didn't report it, or if it's because that traceback is actually from the
>>>> parent stack. If you have a traceback from the original failure in the
>>>> child stack that would be useful. If there's a way to turn on more
>>>> detailed reporting of errors in SQLAlchemy that would also be useful.
>>>>
>>>> Since this is a delete, it's possible that we need a retry-on-deadlock
>>>> on the resource_delete() function also (though resource_update() is
>>>> actually used more during a delete to update the status).
>>>>
>>>> - ZB
>>>>