Re: Shaky coding for vacuuming partitioned relations

On Tue, Sep 26, 2017 at 1:47 AM, Bossart, Nathan <bossartn(at)amazon(dot)com> wrote:
> On 9/24/17, 10:12 PM, "Michael Paquier" <michael(dot)paquier(at)gmail(dot)com> wrote:
>> Attached is a proposal of patch.
>
> The patch seems reasonable to me, and I haven't encountered any issues in
> my tests, even after applying the vacuum-multiple-relations patch on top
> of it.

Thanks for the review, Nathan!

> + * Take a lock here for the relation lookup. If ANALYZE or VACUUM spawn
> + * multiple transactions, the lock taken here will be gone once the
> + * current transaction running commits, which could cause the relation
> + * to be gone, or the RangeVar might not refer to the OID looked up here.
>
> I think this could be slightly misleading. Perhaps it would be more
> accurate to say that the lock will be gone any time vacuum() creates a new
> transaction (either in vacuum_rel() or when use_own_xacts is true).

The comment of the proposed patch matches as much as possible what is
currently on HEAD, so I would still go with something close to that.
--
Michael