Re: pg_basebackup and replication slots

On 22 July 2015 at 05:43, Michael Paquier <michael(dot)paquier(at)gmail(dot)com> wrote:

> Now, do we plan to do something about the creation of a slot. I
> imagine that it would be useful if we could have --create-slot to
> create a slot when beginning a base backup and if-not-exists to
> control the error flow. There is already CreateReplicationSlot for
> this purpose in streamutils.c so most of the work is already done.
> Also, when a base backup fails for a reason or another, we should try
> to drop the slot in disconnect_and_exit() if it has been created by
> pg_basebackup. if if-not-exists is true and the slot already existed
> when beginning, we had better not dropping it perhaps...

What is the purpose of creating a temporary slot?

My understand was that slots are supposed to be persistent so we should
create them before use.

If we create a slot when one is needed and then drop automatically on
session disconnect (as Heikki suggest), what benefit does using a slot give
us?

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