linux-kernel - Re: [PATCH 0/6] Maintain the relative size of fs.file-max and fs.nr

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Message-ID: <20241123182730.GS3387508@ZenIV>
Date: Sat, 23 Nov 2024 18:27:30 +0000
From: Al Viro <viro@...iv.linux.org.uk>
To: Jinliang Zheng <alexjlzheng@...il.com>
Cc: brauner@...nel.org, jack@...e.cz, mcgrof@...nel.org, kees@...nel.org,
	joel.granados@...nel.org, adobriyan@...il.com,
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org,
	flyingpeng@...cent.com, Jinliang Zheng <alexjlzheng@...cent.com>
Subject: Re: [PATCH 0/6] Maintain the relative size of fs.file-max and
 fs.nr_open

On Sun, Nov 24, 2024 at 02:08:55AM +0800, Jinliang Zheng wrote:
> According to Documentation/admin-guide/sysctl/fs.rst, fs.nr_open and
> fs.file-max represent the number of file-handles that can be opened
> by each process and the entire system, respectively.
> 
> Therefore, it's necessary to maintain a relative size between them,
> meaning we should ensure that files_stat.max_files is not less than
> sysctl_nr_open.

NAK.

You are confusing descriptors (nr_open) and open IO channels (max_files).

We very well _CAN_ have more of the former.  For further details,
RTFM dup(2) or any introductory Unix textbook.