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Date:   Tue, 22 Nov 2022 04:59:11 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     "Darrick J. Wong" <djwong@kernel.org>
Cc:     Lukas Czerner <lczerner@redhat.com>,
        Hugh Dickins <hughd@google.com>, Jan Kara <jack@suse.com>,
        Eric Sandeen <sandeen@redhat.com>, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] quota: add quota in-memory format support
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On Mon, Nov 21, 2022 at 09:48:18AM -0800, Darrick J. Wong wrote:
> Would it be wise to "persist" dquot contents to a (private) tmpfs file
> to facilitate incore dquot reclaim?  The tmpfs file data can be paged
> out, or even punched if all the dquot records in that page go back to
> default settings.

That seems like a good idea for memory usage, but I think this might
also make the code much simpler, as that just requires fairly trivial
quota_read and quota_write methods in the shmem code instead of new
support for an in-memory quota file.