Re: [HACKERS] Cannot shutdown subscriber after DROP SUBSCRIPTION

On Wed, Feb 1, 2017 at 5:36 PM, Kyotaro HORIGUCHI
<horiguchi.kyotaro@lab.ntt.co.jp> wrote:
> Hello, while looking another bug, I found that standby cannot
> shutdown after DROP SUBSCRIPTION.
>
> standby=# CREATE SUBSCRPTION sub1 ...
> standby=# ....
> standby=# DROP SUBSCRIPTION sub1;
>
> Ctrl-C to the standby fails to work. ApplyLauncherMain is waiting
> LogicalRepLauncherLock forever.
>
> The culprit is DropSbuscription. It acquires
> LogicalRepLauncherLock but never releases.
>
> The attached patch fixes it. Most part of the fucntion is now
> enclosed by PG_TRY-CATCH since some functions can throw
> exceptions.

The lwlock would be released when an exception occurs, so I don't think
that TRY-CATCH is necessary here. Or it's necessary for another reason?

Regards,

-- 
Fujii Masao