Re: [PATCH] Clarify the behavior of the system when approaching XID wraparound

On Tue, May 2, 2023 at 9:55 AM Peter Geoghegan <pg(at)bowt(dot)ie> wrote:
>
> On Mon, May 1, 2023 at 5:34 AM John Naylor <john(dot)naylor(at)enterprisedb(dot)com>
wrote:

> > 0003 is now a quick-and-dirty attempt at that, only in the docs. The
MXID part is mostly copy-pasted from the XID part, just to get something
together. I'd like to abbreviate that somehow.
>
> Yeah, the need to abbreviate statements about MultiXact IDs by saying
> that they work analogously to XIDs in some particular respect
> is...another thing that makes this tricky.

Then it sounds like they should stay separate. A direct copy-paste is not
good for style, so I will add things like:

- If for some reason autovacuum fails to clear old MXIDs from a table, the
+ As in the case with XIDs, it is possible for autovacuum to fail to [...]

It might least be good for readability to gloss over the warning and only
quote the MXID limit error message, but we'll have to see how it looks.

--
John Naylor
EDB: http://www.enterprisedb.com