Date: Tue, 3 Nov 2020 19:14:47 +0100
From: Dmitry Dolgov <9erthalion6@gmail.com>
To: Michael Paquier <michael@paquier.xyz>
Cc: Alvaro Herrera <alvherre@2ndquadrant.com>,
	James Coleman <jtc331@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>,
	Pg Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: remove spurious CREATE INDEX CONCURRENTLY wait
Message-ID: <20201103181447.54ctwnfdt5wztbqn@localhost>
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 <20200819181646.GA1559@alvherre.pgsql>
 <20200820060929.GB3730@paquier.xyz>
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> On Thu, Aug 20, 2020 at 03:11:19PM +0900, Michael Paquier wrote:
> On Wed, Aug 19, 2020 at 02:16:46PM -0400, Alvaro Herrera wrote:
> > I did not set the flag in REINDEX CONCURRENTLY, but as I understand it
> > can be done too, since in essence it's the same thing as a CIC from a
> > snapshot management point of view.
>
> Yes, I see no problems for REINDEX CONCURRENTLY as well as long as
> there are no predicates and expressions involved.  The transactions
> that should be patched are all started in ReindexRelationConcurrently.
> The transaction of index_concurrently_swap() cannot set up that
> though.  Only thing to be careful is to make sure that safe_flag is
> correct depending on the list of indexes worked on.

Hi,

After looking through the thread and reading the patch it seems good,
and there are only few minor questions:

* Doing the same for REINDEX CONCURRENTLY, which does make sense. In
  fact it's already mentioned in the commentaries as done, which a bit
  confusing.

* Naming, to be more precise what suggested Michael:

> Could we consider renaming vacuumFlags?  With more flags associated to
> a PGPROC entry that are not related to vacuum, the current naming
> makes things confusing.  Something like statusFlags could fit better
> in the picture?

  which sounds reasonable, and similar one about flag name
  PROC_IN_SAFE_CIC - if it covers both CREATE INDEX/REINDEX CONCURRENTLY
  maybe just PROC_IN_SAFE_IC?

Any plans about those questions? I can imagine that are the only missing
parts.