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From: Jelte Fennema-Nio <postgres@jeltef.nl>
Date: Sat, 8 Feb 2025 14:54:14 +0100
Message-ID: <CAGECzQRvcLx44N3zd_DGCjY02XX4AqXX8mq4BiS8C9Froy+Jhg@mail.gmail.com>
Subject: Re: RFC: Allow EXPLAIN to Output Page Fault Information
To: torikoshia <torikoshia@oss.nttdata.com>
Cc: pgsql-hackers@postgresql.org, rjuju123@gmail.com, tgl@sss.pgh.pa.us, 
	Bruce Momjian <bruce@momjian.us>
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On Mon, 27 Jan 2025 at 10:05, torikoshia <torikoshia@oss.nttdata.com> wrote:
> Therefore, I believe it would be reasonable to report the raw values
> as-is, as they should still be useful for understanding storage I/O
> activity.

Sounds reasonable.

Below some feedback on the patch. It's all really minor. The patch
looks great. I'll play around with it a bit next week.

meta: it's confusing that this one is called v1 again, it would be
clearer if it was called v2.

nit: at line 528 the "if (es->buffers)" check can simply be merged
with the if block above (which does the exact same check)

> if (usage->inblock <= 0 && usage->outblock <= 0)
>     return false;
>
> else
>    return true;

nit: You can replace that if-else with:
return usage->inblock > 0 || usage->outblock > 0;

> StorageIOUsageAccumDiff(StorageIOUsage *dst, const StorageIOUsage *add, const StorageIOUsage *sub)

Missing a function comment