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Date:   Thu, 2 May 2019 14:26:23 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Theodore Ts'o <tytso@mit.edu>
Cc:     Amir Goldstein <amir73il@gmail.com>, ezemtsov@google.com,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: Initial patches for Incremental FS
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On Thu, May 02, 2019 at 09:10:34AM -0400, Theodore Ts'o wrote:

> +Why isn't incremental-fs implemented via FUSE?
> +----------------------------------------------
> +TLDR: FUSE-based filesystems add 20-80% of performance overhead for target
> +scenarios, and increase power use on mobile beyond acceptable limit
> +for widespread deployment. A custom kernel filesystem is the way to overcome
> +these limitations.
> +
> 
> There are several paragraphs of more detail which I leave for the
> interested reader to review....

Why not CODA, though, with local fs as cache?