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Date:   Tue, 19 Oct 2021 15:44:10 +0800
From:   Ming Lei <ming.lei@redhat.com>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Lennart Poettering <lennart@poettering.net>,
        Jens Axboe <axboe@fb.com>, Martijn Coenen <maco@android.com>,
        linux-block@vger.kernel.org, Luca Boccassi <bluca@debian.org>,
        Karel Zak <kzak@redhat.com>
Subject: Re: Is LO_FLAGS_DIRECT_IO by default a good idea?
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 <20211018150550.GA29993@lst.de>
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On Mon, Oct 18, 2021 at 05:05:50PM +0200, Christoph Hellwig wrote:
> On Mon, Oct 18, 2021 at 04:19:20PM +0200, Lennart Poettering wrote:
> > A brief answer like "yes, please, enable by default" would already
> > make me happy.
> 
> I thikn enabling it by default is a good idea.  The only good use
> case I can think of for using buffered I/O is when the image has
> a smaller block size than supported on the host file.

Maybe we can enable it at default in kernel side, then fackback to
buffered IO if DIO is failed.

thanks, 
Ming