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Date:   Mon, 21 Sep 2020 20:18:41 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Coly Li <colyli@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        Song Liu <song@kernel.org>,
        Hans de Goede <hdegoede@redhat.com>,
        Richard Weinberger <richard@nod.at>,
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Subject: Re: [PATCH 03/13] bcache: inherit the optimal I/O size
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On Mon, Sep 21, 2020 at 11:09:48PM +0800, Coly Li wrote:
> I feel this is something should be fixed. Indeed I overlooked it until
> you point out the issue now.
> 
> The optimal request size and read ahead pages hint are necessary, but
> current initialization is simple. A better way might be dynamically
> setting them depends on the cache mode and some special configuration.
> 
> By your inspiration, I want to ACK your original patch although it
> doesn't work fine for all condition. Then we may know these two settings
> (ra_pages and queue_io_opt) should be improved for more situations. At
> lease for most part of the situations they provide proper hints.
> 
> How do you think of the above idea ?

Sounds like a plan.  I'd reall like to get this series in to get
some soaking before the end of the merge window, but we should still
have plenty of time for localized bcache updates.