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Date:   Mon, 17 Apr 2023 21:31:20 -0700 (PDT)
From:   Hugh Dickins <hughd@google.com>
To:     Luis Chamberlain <mcgrof@kernel.org>
cc:     hughd@google.com, akpm@linux-foundation.org, willy@infradead.org,
        brauner@kernel.org, linux-mm@kvack.org, p.raghav@samsung.com,
        da.gomez@samsung.com, a.manzanares@samsung.com, dave@stgolabs.net,
        yosryahmed@google.com, keescook@chromium.org,
        patches@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/6] tmpfs: add the option to disable swap
In-Reply-To: <20230309230545.2930737-1-mcgrof@kernel.org>
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References: <20230309230545.2930737-1-mcgrof@kernel.org>
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On Thu, 9 Mar 2023, Luis Chamberlain wrote:

> I'm doing this work as part of future experimentation with tmpfs and the
> page cache, but given a common complaint found about tmpfs is the
> innability to work without the page cache I figured this might be useful
> to others. It turns out it is -- at least Christian Brauner indicates
> systemd uses ramfs for a few use-cases because they don't want to use
> swap and so having this option would let them move over to using tmpfs
> for those small use cases, see systemd-creds(1).

Thanks for your thorough work on tmpfs "noswap": seems well-received
by quite a few others, that's good.

I've just a few comments on later patches (I don't understand why you
went into those little rearrangements at the start of shmem_writepage(),
but they seem harmless so I don't object), but wanted to ask here:

You say "a common complaint about tmpfs is the inability to work without
the page cache".  Ehh?  I don't understand that at all, and have never
heard such a complaint.  It doesn't affect the series itself (oh, Andrew
has copied that text into the first patch), but please illuminate!

Thanks,
Hugh