Re: 035_standby_logical_decoding unbounded hang

Hi,

On Thu, Feb 15, 2024 at 12:48:16PM -0800, Noah Misch wrote:
> On Wed, Feb 14, 2024 at 03:31:16PM +0000, Bertrand Drouvot wrote:
> > What about creating a sub, say wait_for_restart_lsn_calculation() in Cluster.pm
> > and then make use of it in create_logical_slot_on_standby() and above? (something
> > like wait_for_restart_lsn_calculation-v1.patch attached).
>
> Waiting for restart_lsn is just a prerequisite for calling
> pg_log_standby_snapshot(), so I wouldn't separate those two.

Yeah, makes sense.

> If we're
> extracting a sub, I would move the pg_log_standby_snapshot() call into the sub
> and make the API like one of these:
>
> $standby->wait_for_subscription_starting_point($primary, $slot_name);
> $primary->log_standby_snapshot($standby, $slot_name);
>
> Would you like to finish the patch in such a way?

Sure, please find attached standby-slot-test-2-race-v2.patch doing so. I used
log_standby_snapshot() as it seems more generic to me.

Regards,

--
Bertrand Drouvot
PostgreSQL Contributors Team
RDS Open Source Databases
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