Re: VACUUM PARALLEL option vs. max_parallel_maintenance_workers

On 2020-09-19 11:37, Amit Kapila wrote:
> I think we can change the documentation for parallel option to explain
> it better. How about: "Perform index vacuum and index cleanup phases
> of VACUUM in parallel using integer background workers (for the
> details of each vacuum phase, please refer to Table 27.37). The number
> of workers is determined based on the number of indexes on the
> relation that support parallel vacuum operation which is limited by
> number of workers specified with PARALLEL option if any which is
> further limited by max_parallel_maintenance_workers." instead of what
> is currently there?

I think the implemented behavior is wrong.  The VACUUM PARALLEL option 
should override the max_parallel_maintenance_worker setting.

Otherwise, what's the point of the command option?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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