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From:   David Howells <dhowells@redhat.com>
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To:     Miklos Szeredi <miklos@szeredi.hu>
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
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        Trond Myklebust <trond.myklebust@hammerspace.com>,
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Subject: Re: [PATCH 00/13] VFS: Filesystem information [ver #19]
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Date:   Wed, 01 Apr 2020 09:27:29 +0100
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Miklos Szeredi <miklos@szeredi.hu> wrote:

> According to dhowell's measurements processing 100k mounts would take
> about a few seconds of system time (that's the time spent by the
> kernel to retrieve the data,

But the inefficiency of mountfs - at least as currently implemented - scales
up with the number of individual values you want to retrieve, both in terms of
memory usage and time taken.

With fsinfo(), I've tried to batch values together where it makes sense - and
there's no lingering memory overhead - no extra inodes, dentries and files
required.

David