Re: optimizing pg_upgrade's once-in-each-database steps

On Fri, Jul 19, 2024 at 04:21:37PM -0500, Nathan Bossart wrote:
> However, while looking into this, I noticed that only one get_query
> callback (get_db_subscription_count()) actually customizes the generated
> query using information in the provided DbInfo. AFAICT we can do this
> particular step without running a query in each database, as I mentioned
> elsewhere [0]. That should speed things up a bit and allow us to simplify
> the AsyncTask code.
>
> With that, if we are willing to assume that a given get_query callback will
> generate the same string for all databases (and I think we should), we can
> run the callback once and save the string in the step for dispatch_query()
> to use. This would look more like what you suggested in the quoted text.

Here is a new patch set. I've included the latest revision of the patch to
fix get_db_subscription_count() from the other thread [0] as 0001 since I
expect that to be committed soon. I've also moved the patch that moves the
"live_check" variable to "user_opts" to 0002 since I plan on committing
that sooner than later, too. Otherwise, I've tried to address all feedback
provided thus far.

[0] https://commitfest.postgresql.org/49/5135/

--
nathan