Re: [PATCH] vfs: make open_with_fake_path() not contribute to nr_files

From: David Howells
Date: Thu Jul 19 2018 - 04:09:23 EST


Miklos Szeredi <mszeredi@xxxxxxxxxx> wrote:

> Stacking file operations in overlay will store an extra open file for each
> overlay file opened.
>
> The overhead is just that of "struct file" which is about 256bytes, because
> overlay already pins an extra dentry and inode when the file is open, which
> add up to a much larger overhead.
>
> For fear of breaking working setups, don't start accounting the extra file.

Sounds useful for cachefiles too, though Christoph Hellwig objected strongly
last time I tried this, so you might want to check with him directly.

David