Re: [HACKERS] Regression stoping PostgreSQL 9.4.13 if a walsender is running

On Wed, Aug 23, 2017 at 2:28 AM, Marco Nenciarini
<marco.nenciarini@2ndquadrant.it> wrote:
> I have noticed that after the 9.4.13 release PostgreSQL reliably fails
> to shutdown with smart and fast method if there is a running walsender.
>
> The postmaster continues waiting forever for the walsender termination.
>
> It works perfectly with all the other major releases.

Right. A similar issue has been reported yesterday:
https://www.postgresql.org/message-id/CAA5_DuD0O1XyM8OnOzhRepyPU-t8nZKLzs1pT2JpzP0NS+vVNA@mail.gmail.com
Thanks for digging into the origin of the problem, I was lacking of
time yesterday to look at it.

> I bisected the issue to commit 1cdc0ab9c180222a94e1ea11402e728688ddc37d
>
> After some investigation I discovered that the instruction that sets
> got_SIGUSR2 was lost during the backpatch in the WalSndLastCycleHandler
> function.

That looks correct to me, only REL9_4_STABLE is impacted. This bug
breaks many use cases like failovers :(
-- 
Michael