Date: Sat, 17 Jan 2026 01:31:32 +0100
From: Christoph Berg <myon@debian.org>
To: Tomas Vondra <tomas@vondra.me>
Cc: Jakub Wartak <jakub.wartak@enterprisedb.com>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: failed NUMA pages inquiry status: Operation not permitted
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Re: Tomas Vondra
> Here's WIP fix for the root cause, i.e. handling status -2 in the two
> views querying NUMA node for memory pages:

Thanks!

> I'm not sure if we need to mention this in the docs. It probably should
> mention the column can be NULL, which means "unknown node".

We could simply say

  The returned value can be NULL if the NUMA node cannot be
  determined, e.g. when the page has been swapped out.

> Subject: [PATCH] Handle ENOENT status when querying NUMA node
...
> We touch the memory before querying the status, but there is no
> guarangee it won't be moved to swap in between. We do the touching only
  ^ guarantee

Christoph