Re: [HACKERS] Get stuck when dropping a subscription duringsynchronizing table

On 01/06/17 17:32, Masahiko Sawada wrote:
> On Thu, May 25, 2017 at 5:29 PM, tushar <tushar.ahuja@enterprisedb.com> wrote:
>> On 05/25/2017 12:44 AM, Petr Jelinek wrote:
>>>
>>> There is still outstanding issue that sync worker will keep running
>>> inside the long COPY because the invalidation messages are also not
>>> processed until it finishes but all the original issues reported here
>>> disappear for me with the attached patches applied.
>>
>> After applying all your patches, drop subscription no  more hangs while
>> dropping  subscription but there is an error   "ERROR:  tuple concurrently
>> updated" in the log file of
>> standby.
>>
> 
> I tried to reproduce this issue with latest four patches I submit but
> it didn't happen. I guess this issue doesn't related to the issues
> reported on this thread and another factor  might be cause of this
> issue. It would be good to test the same again with latest four
> patches or after solved current some open items.
> 

That's because your additional patch kills the workers that do the
concurrent update. While that's probably okay, I still plan to look into
making the subscription and state locking more robust.

--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
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