Re: VACUUM memory management

On Wed, Dec 11, 2019 at 7:29 PM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Mon, Dec 9, 2019 at 2:02 PM Ibrar Ahmed <ibrar(dot)ahmad(at)gmail(dot)com> wrote:
> >> Did you see this thread?
> >>
> https://postgr.es/m/CAGTBQpbDCaR6vv9=scXzuT8fSbckf=a3NgZdWFWZbdVugVht6Q@mail.gmail.com
> >>
> > Yes, and somehow did what is explained.
>
> Did you modify Claudio's patch or write a totally new one?

I wrote completely new patch. I tried multiple techniques like using a list
instead of fixed size array which I thought was most suitable here, but
leave that because of conflict with Parallel Vacuum.

> In either case, why did you choose that approach?

This is the simplest technique. I just divided the maintenance_work_mem in
chunks and allocate chunks as needed. This technique change minimum code
and do what we want to achieve.

> If you wrote a totally new one, have you compared your work with
> Claudio's, to see if he covered
> anything you might need to cover?

No, this part I missed, I will do that and will share my thoughts.

> Please explain why your patch is
> better/different than his.
>
>

> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>

--
Ibrar Ahmed