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

On 2017-05-08 11:27, Masahiko Sawada wrote:
> Hi,
> 
> I encountered a situation where DROP SUBSCRIPTION got stuck when
> initial table sync is in progress. In my environment, I created
> several tables with some data on publisher. I created subscription on
> subscriber and drop subscription immediately after that. It doesn't
> always happen but I often encountered it on my environment.
> 
> ps -x command shows the following.
> 
>  96796 ?        Ss     0:00 postgres: masahiko postgres [local] DROP
> SUBSCRIPTION
>  96801 ?        Ts     0:00 postgres: bgworker: logical replication
> worker for subscription 40993    waiting
>  96805 ?        Ss     0:07 postgres: bgworker: logical replication
> worker for subscription 40993 sync 16418
>  96806 ?        Ss     0:01 postgres: wal sender process masahiko 
> [local] idle
>  96807 ?        Ss     0:00 postgres: bgworker: logical replication
> worker for subscription 40993 sync 16421
>  96808 ?        Ss     0:00 postgres: wal sender process masahiko 
> [local] idle
> 

FWIW, running

> 0001-WIP-Fix-off-by-one-around-GetLastImportantRecPtr.patch+
> 0002-WIP-Possibly-more-robust-snapbuild-approach.patch     +
> fix-statistics-reporting-in-logical-replication-work.patch    (on top of 44c528810)

I have encountered the same condition as well in the last few days, a 
few times (I think 2 or 3 times).

Erik Rijkers