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Date:   Mon, 10 Jul 2023 17:21:04 -0700
From:   Luis Chamberlain <mcgrof@kernel.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org,
        Wang Yugui <wangyugui@e16-tech.com>,
        Dave Chinner <david@fromorbit.com>,
        Christoph Hellwig <hch@infradead.org>,
        "Darrick J . Wong" <djwong@kernel.org>,
        Kent Overstreet <kent.overstreet@linux.dev>,
        Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH v4 7/9] filemap: Allow __filemap_get_folio to allocate
 large folios
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On Tue, Jul 11, 2023 at 01:07:37AM +0100, Matthew Wilcox wrote:
> The caller hints at the
> folio size it wants, and this code you're highlighting limits it to be
> less than MAX_PAGECACHE_ORDER.

Yes sorry, if the write size is large we still max out at MAX_PAGECACHE_ORDER
naturally. I don't doubt the rationale that that is a good idea.

What I'm curious about is why are we OK to jump straight to MAX_PAGECACHE_ORDER
from the start and if there are situations where perhaps a a
not-so-aggressive high order may be desriable. How do we know?

  Luis