Re: Detecting File Damage & Inconsistencies

On Fri, 2 Jul 2021 at 00:19, Simon Riggs <simon(dot)riggs(at)enterprisedb(dot)com>
wrote:

> > So yeah. I think it'd be better to log the info you want at start-of-txn
> unless there's a compelling reason not so, and I don't see one yet.
>
> AFAIK, XLOG_XACT_ASSIGNMENT does not occur for normal top-level
> transactions, only for subxids.
>
> I don't really want to add an extra record just for this because it
> will slow down applications and it won't get turned on as often.
>

OK, that makes sense - I was indeed operating on an incorrect assumption.

I wouldn't want to add a new record either. I thought we could piggyback on
XLOG_XACT_ASSIGNMENT with a new chunk that's only added when the feature is
required, much like we do for replication origin info on commit records.

Is it worth considering forcing XLOG_XACT_ASSIGNMENT to be logged if this
feature is enabled?

If you don't think the sorts of use cases I presented are worth the trouble
that's fair enough. I'm not against adding it on the commit record. It's
just that with logical decoding moving toward a streaming model I suspect
only having it at commit time may cause us some pain later.