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Subject: Re: [PATCH] block: BFQ default for single queue devices
From: Artem Bityutskiy <dedekind1@gmail.com>
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To: Paolo Valente <paolo.valente@linaro.org>, Jens Axboe <axboe@kernel.dk>
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 <aherrmann@suse.com>, Mel Gorman <mgorman@suse.com>, Chunyan Zhang
 <zhang.chunyan@linaro.org>, linux-kernel <linux-kernel@vger.kernel.org>,
 'Paolo Valente' via bfq-iosched <bfq-iosched@googlegroups.com>, Oleksandr
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Date: Wed, 03 Oct 2018 10:05:25 +0300
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On Wed, 2018-10-03 at 08:29 +0200, Paolo Valente wrote:
> So, I do understand your need for conservativeness, but, after so much
> evidence on single-queue devices, and so many years! :), what's the
> point in keeping Linux worse for virtually everybody, by default?

Sounds like what we just need a mechanism for the device (ubi block in
this case) to select the I/O scheduler. I doubt enhancing the default
scheduler selection logic in 'elevator.c' is the right answer. Just
give the driver authority to override the defaults.