RE: ReplicationSlotRelease() crashes when the instance is in the single user mode

Dear Robert,

> The use case for single-user mode is quite limited in general, but
> most things work in single-user mode unless they are something that
> intrinsically can't. For example, parallel query cannot be used in
> single-user mode, because there is only one process. Replication
> cannot work, for the same reason. But manual slot operations can work,
> so I do not think it is good to arbitrarily prohibit them. We do not
> need a reason to specifically allow them; it is enough that there is
> no good reason for them to be blocked.

Thanks for the confirmation. Till now, it is mostly fifty-fifty in the community
whether we should allow the manipulation in the single-user mode.

I did split a patch to fix the initial issue [1]. Let's focus on the 0001 patch
firstly.

[1]:
https://www.postgresql.org/message-id/OSCPR01MB14966B39B3ED21229EAEFA10FF531A%40OSCPR01MB14966.jpnprd01.prod.outlook.com

Best regards,
Hayato Kuroda
FUJITSU LIMITED