Date: Wed, 26 Mar 2025 14:21:15 -0700
From: Noah Misch <noah@leadboat.com>
To: Andres Freund <andres@anarazel.de>
Cc: Antonin Houska <ah@cybertec.at>, pgsql-hackers@postgresql.org,
	Thomas Munro <thomas.munro@gmail.com>,
	Heikki Linnakangas <hlinnaka@iki.fi>,
	Robert Haas <robertmhaas@gmail.com>,
	Jakub Wartak <jakub.wartak@enterprisedb.com>,
	Jelte Fennema-Nio <postgres@jeltef.nl>
Subject: Re: AIO v2.5
Message-ID: <20250326212115.ab.nmisch@google.com>
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On Wed, Mar 26, 2025 at 04:33:49PM -0400, Andres Freund wrote:
> On 2025-03-25 17:19:15 -0700, Noah Misch wrote:
> > On Mon, Mar 24, 2025 at 09:18:06PM -0400, Andres Freund wrote:

> > Second, the aio_internal.h comment changes discussed in
> > postgr.es/m/20250325155808.f7.nmisch@google.com and earlier.
> 
> Here's my current version of that:
> 
>  * Note that the externally visible functions to start IO
>  * (e.g. FileStartReadV(), via pgaio_io_start_readv()) move an IO from
>  * PGAIO_HS_HANDED_OUT to at least PGAIO_HS_STAGED and at most
>  * PGAIO_HS_COMPLETED_LOCAL (at which point the handle will be reused).
> 
> Does that work?

Yes.

> I think I'll push that as part of the comment updates patch instead of
> "Implement support for reads in smgr/md/fd", unless you see a reason to do so
> differently. I'd have done it in the patch to s/prep/start/, but then it would
> reference functions that don't exist yet...

Agreed.

> > > Subject: [PATCH v2.12 06/28] aio: Add README.md explaining higher level design
> > 
> > Ready for commit
> 
> Cool.
> 
> Comments in it reference PGAIO_HCB_SHARED_BUFFER_READV, so I'm inclined to
> reorder it until after "bufmgr: Implement AIO read support".

Agreed.

> > For example, this local variable could become add_to_nblocks_done instead.
> 
> I named it "newly_read_blocks", hope that works?

Yes.