Re: [HACKERS] Block level parallel vacuum

On Mon, 18 Nov 2019 at 15:34, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Mon, Nov 18, 2019 at 11:37 AM Masahiko Sawada
> <masahiko(dot)sawada(at)2ndquadrant(dot)com> wrote:
> >
> > On Wed, 13 Nov 2019 at 14:31, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> > >
> > >
> > > Based on these needs, we came up with a way to allow users to specify
> > > this information for IndexAm's. Basically, Indexam will expose a
> > > variable amparallelvacuumoptions which can have below options
> > >
> > > VACUUM_OPTION_NO_PARALLEL 1 << 0 # vacuum (neither bulkdelete nor
> > > vacuumcleanup) can't be performed in parallel
> >
> > I think VACUUM_OPTION_NO_PARALLEL can be 0 so that index AMs who don't
> > want to support parallel vacuum don't have to set anything.
> >
>
> make sense.
>
> > > VACUUM_OPTION_PARALLEL_BULKDEL 1 << 1 # bulkdelete can be done in
> > > parallel (Indexes nbtree, hash, gin, gist, spgist, bloom will set this
> > > flag)
> > > VACUUM_OPTION_PARALLEL_COND_CLEANUP 1 << 2 # vacuumcleanup can be
> > > done in parallel if bulkdelete is not performed (Indexes nbtree, brin,
> > > gin, gist,
> > > spgist, bloom will set this flag)
> > > VACUUM_OPTION_PARALLEL_CLEANUP 1 << 3 # vacuumcleanup can be done in
> > > parallel even if bulkdelete is already performed (Indexes gin, brin,
> > > and bloom will set this flag)
> >
> > I think gin and bloom don't need to set both but should set only
> > VACUUM_OPTION_PARALLEL_CLEANUP.
> >
> > And I'm going to disallow index AMs to set both
> > VACUUM_OPTION_PARALLEL_COND_CLEANUP and VACUUM_OPTION_PARALLEL_CLEANUP
> > by assertions, is that okay?
> >
>
> Sounds reasonable to me.
>
> Are you planning to include the changes related to I/O throttling
> based on the discussion in the nearby thread [1]? I think you can do
> that if you agree with the conclusion in the last email[1], otherwise,
> we can explore it separately.

Yes I agreed. I'm going to include that changes in the next version
patches. And I think we will be able to do more discussion based on
the patch.

Regards,

--
Masahiko Sawada http://www.2ndQuadrant.com/
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