Re: Add 64-bit XIDs into PostgreSQL 15

Hi,

On 2022-11-21 14:21:35 -0500, Tom Lane wrote:
> Peter Eisentraut <peter.eisentraut@enterprisedb.com> writes:
> >> To date testing database cluster wraparund was not easy as initdb has always
> >> inited it with default xid/mxid/mxoff. The option to specify any valid
> >> xid/mxid/mxoff at cluster startup will make these things easier.
>
> > Doesn't pg_resetwal already provide that functionality, or at least some
> > of it?
>
> pg_resetwal does seem like a better, more useful home for this; it'd
> allow you to adjust these numbers after initial creation which might be
> useful.  I'm not sure how flexible it is right now in terms of where
> you can set the new values, but that can always be improved.

IIRC the respective pg_resetwal parameters are really hard to use for
something like this, because they don't actually create the respective
SLRU segments. We of course could fix that.

Greetings,

Andres Freund