Re: [HACKERS] Block level parallel vacuum

On Sun, Dec 1, 2019 at 11:01 PM Sergei Kornilov <sk@zsrv.org> wrote:
>
> Hi
>
> > I think I got your point. Your proposal is that it's more efficient if
> > we make the leader process vacuum the index that can be processed only
> > the leader process (i.e. indexes not supporting parallel index vacuum)
> > while workers are processing indexes supporting parallel index vacuum,
> > right? That way, we can process indexes in parallel as much as
> > possible.
>
> Right
>
> > So maybe we can call vacuum_or_cleanup_skipped_indexes first
> > and then call vacuum_or_cleanup_indexes_worker. But I'm not sure that
> > there are parallel-safe remaining indexes after the leader finished
> > vacuum_or_cleanup_indexes_worker, as described on your proposal.
>
> I meant that after processing missing indexes (not supporting parallel index vacuum), the leader can start processing
indexesthat support the parallel index vacuum, along with parallel workers.
 
> Exactly call vacuum_or_cleanup_skipped_indexes after start parallel workers but before
vacuum_or_cleanup_indexes_workeror something with similar effect.
 
> If we have 0 missed indexes - parallel vacuum will run as in current implementation, with leader participation.

+1

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com