回复：Re: speed up pg_upgrade with large number of tables

> > So, I'm thinking, why not add a "--skip-check" option in pg_upgrade to skip it?
> > See "1-Skip_Compatibility_Check_v1.patch".
>
> How would a user know that nothing has changed in the cluster between running
> the check and running the upgrade with a skipped check? Considering how
> complicated it is to understand exactly what pg_upgrade does it seems like
> quite a large caliber footgun.
Indeed, it's not feasible to execute an concise check ensuring that nothing
has changed. However, in many cases, a cluster consistently executes the
same SQL commands. Thus, if we've verified that the cluster was compatible
30 minutes prior, there's a strong likelihood that it remains compatible now.
Therefore, adding such an 'trust-me' option may still be beneficial.

> I would be much more interested in making the check phase go faster, and indeed
> there is ongoing work in this area. Since it sounds like you have a dev and
> test environment with a big workload, testing those patches would be helpful.
> https://commitfest.postgresql.org/48/4995/ is one that comes to mind.
Very meaningful work! I will try it.

--
Best regards,
Yang Boyu