Re: VACUUM PARALLEL option vs. max_parallel_maintenance_workers

On Sat, Oct 3, 2020 at 9:25 AM Masahiko Sawada
<masahiko.sawada@2ndquadrant.com> wrote:
> To make the behavior of parallel vacuum more consistent with other
> parallel maintenance commands (i.g., only parallel INDEX CREATE for
> now), as a second idea, can we make use of parallel_workers reloption
> in parallel vacuum case as well?

That seems like a terrible idea to me. I don't see why the number of
workers that some user thinks should be used to perform a scan on the
table as part of the query should be the same as the number of workers
that should be used for a maintenance operation. We get in trouble
every time we try to reuse a setting for an unrelated purpose.

-- 
Robert Haas
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