Re: BUG #13443: master will remove dead rows when hot standby(use slot) disconnect

On Mon, Jun 15, 2015 at 2:05 AM, <digoal(at)126(dot)com> wrote:

> The following bug has been logged on the website:
>
> Bug reference: 13443
> Logged by: digoal
> Email address: digoal(at)126(dot)com
> PostgreSQL version: Unsupported/Unknown
>

Does that mean you are using 9.5dev? If so, do you see the same behavior
in 9.4.4?

> Operating system: CentOS 6.x x64
> Description:
>
>
> http://www.postgresql.org/docs/devel/static/warm-standby.html#STREAMING-REPLICATION
>
> 25.2.6. Replication Slots
> Replication slots provide an automated way to ensure that the master does
> not remove WAL segments until they have been received by all standbys, and
> that the master does not remove rows which could cause a recovery conflict
> even when the standby is disconnected.
>
> In my test, master will remove rows when standby disconnect.
>

I can't reproduce this. In my hands when the standby crashes, tuples on
the master are not removed until either that slot is destroyed on the
master, or until the standby reconnects.

Can you show us all the settings changes you have made to postgresql.conf
and recovery.conf, and to the replication slots table?

One potential doc bug I see is that the it seems to imply that replication
slots replaces the need for hot_standby_feedback, when it fact it must be
used in conjunction with it. Do you have hot_standby_feedback turned on in
the standby?

Cheers,

Jeff