Re: Sketch of a fix for that truncation data corruption issue

Greetings,

* Andres Freund (andres(at)anarazel(dot)de) wrote:
> On 2018-12-10 15:38:55 -0500, Tom Lane wrote:
> > Also, I'm not entirely sure whether there's anything in our various
> > replication logic that's dependent on vacuum truncation taking AEL.
> > Offhand I'd expect the reduced use of AEL to be a plus, but maybe
> > I'm missing something.
>
> It'd be a *MAJOR* plus. One of the biggest operational headaches for
> using a HS node for querying is that there'll often be conflicts due to
> vacuum truncating relations (which logs an AEL), even if
> hot_standby_feedback is used. There's been multiple proposals to
> allow disabling truncations just because of that.

Huge +1 from me here, we've seen this too. Getting rid of the conflict
when using a HS node for querying would be fantastic.

Thanks!

Stephen