Re: BUG #17717: Regression in vacuumdb (15 is slower than 10/11 and possible memory issue)

Nathan Bossart <nathandbossart@gmail.com>

From: Nathan Bossart <nathandbossart@gmail.com>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: Peter Geoghegan <pg@bowt.ie>, postgresql@taljaren.se, pgsql-hackers@lists.postgresql.org, Michael Paquier <michael@paquier.xyz>

Date: 2022-12-28T21:12:53Z

Lists: pgsql-bugs, pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Add options to control whether VACUUM runs vac_update_datfrozenxid.
- a46a7011b271 16.0 landed
Use catalog query to discover tables to process in vacuumdb
- e0c2933a767c 12.0 cited

Attachments

v1-0001-add-UPDATE_DATFROZENXID-option-to-VACUUM.patch (text/x-diff)

On Wed, Dec 28, 2022 at 03:13:23PM -0500, Tom Lane wrote:
> I'm forced to the conclusion that we have to expose some VACUUM
> options if we want this to work well.  Attached is a draft patch
> that invents SKIP_DATABASE_STATS and ONLY_DATABASE_STATS options
> (name bikeshedding welcome) and teaches vacuumdb to use them.

This is the conclusion I arrived at, too.  In fact, I was just about to
post a similar patch set.  I'm attaching it here anyway, but I'm fine with
proceeding with your version.

I think the main difference between your patch and mine is that I've
exposed vac_update_datfrozenxid() via a function instead of a VACUUM
option.  IMHO that feels a little more natural, but I can't say I feel too
strongly about it.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com