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Date: Thu, 4 Oct 2018 20:25:53 +0100
From: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To: Bart Van Assche <bvanassche@acm.org>
Cc: Paolo Valente <paolo.valente@linaro.org>, Jens Axboe <axboe@kernel.dk>,
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 <bfq-iosched@googlegroups.com>, Oleksandr Natalenko
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Subject: Re: [PATCH] block: BFQ default for single queue devices
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> I agree with Jens that it's best to leave it to the Linux distributors to
> select a default I/O scheduler.

That assumes such a thing exists. The kernel knows what devices it is
dealing with. The kernel 'default' ought to be 'whatever is usually best
for this device'. A distro cannot just pick a correct single default
because NVME and USB sticks are both normal and rather different in needs.

Alan