Re: [HACKERS] Refreshing subscription relation state inside atransaction block

On Thu, Jul 27, 2017 at 9:31 AM, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> On Wed, Jul 26, 2017 at 10:29 PM, Robert Haas <robertmhaas@gmail.com> wrote:
>> On Mon, Jun 19, 2017 at 4:30 AM, Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>>>> I think that either of the options you suggested now would be better.
>>>> We'll need that for stopping the tablesync which is in progress during
>>>> DropSubscription as well as those will currently still keep running. I
>>>> guess we could simply just register syscache callback, the only problem
>>>> with that is we'd need to AcceptInvalidationMessages regularly while we
>>>> do the COPY which is not exactly free so maybe killing at the end of
>>>> transaction would be better (both for refresh and drop)?
>>>
>>> Attached patch makes table sync worker check its relation subscription
>>> state at the end of COPY and exits if it has disappeared, instead of
>>> killing table sync worker in DDL. There is still a problem that a
>>> table sync worker for a large table can hold a slot for a long time
>>> even after its state is deleted. But it would be for PG11 item.
>>
>> Do we still need to do something about this?  Should it be an open item?
>>
>
> Thank you for looking at this.
>
> Yeah, I think it should be added to the open item list. The patch is
> updated by Petr and discussed on another thread[1] that also addresses
> other issues of subscription codes. 0004 patch of that thread is an
> updated patch of the patch attached on this thread.
>

Does anyone have any opinions? Barring any objections, I'll add this
to the open item list.

Regards,

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