Doubt about AccessExclusiveLock in ALTER TABLE .. SET ( .. );

Hi all,

I'm tweaking some autovacuum settings in a table with high write usage but
with ALTER TABLE .. SET ( .. ) this task was impossible, so I did a catalog
update (pg_class) to change reloptions.

Maybe it's a stupid doubt, but why we need to get an AccessExclusiveLock on
relation to set reloptions if we just touch in pg_class tuples
(RowExclusiveLock) ?

Regards,

--
Fabrízio de Royes Mello
Consultoria/Coaching PostgreSQL
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