Re: [HACKERS] pg_subscription_rel entry can be updated concurrently

On Tue, Jun 13, 2017 at 2:55 PM, Petr Jelinek
<petr.jelinek@2ndquadrant.com> wrote:
> On 13/06/17 02:52, Masahiko Sawada wrote:
>> Hi,
>>
>> I often get an error "ERROR:  tuple concurrently updated" when
>> changing subscription state(ALTER SUBSCRIPTION or DROP SUBSCRIPTION).
>> The cause of this error is that table sync worker and apply worker can
>> try to update the same tuple in pg_subscription_rel. Especially it
>> often happens when we do initial copy for many tables and change it
>> during executing.
>>
>> I think that touching the same tuple by two worker processes happens
>> when aborting replication for a table or a subscription, so it would
>> be the same result as when the worker ends up with an error. But I
>> think since it's not an appropriate behavior we should deal with it.
>> Any thoughts?
>>
>
> This has been already reported by tushar in different thread and it's
> still on my list to fix.
>

Okay, I see. I added it to the open item list.

Regards,

--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center