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([2620:15c:2cd:203:5cdc:422c:7b28:ebb5]) by smtp.gmail.com with ESMTPSA id u9-v6sm5804193pfi.104.2018.10.03.09.00.47 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 03 Oct 2018 09:00:47 -0700 (PDT) Message-ID: <1538582446.205649.22.camel@acm.org> Subject: Re: [PATCH] block: BFQ default for single queue devices From: Bart Van Assche To: Paolo Valente , Oleksandr Natalenko Cc: Jens Axboe , Linus Walleij , linux-block , linux-mmc , linux-mtd@lists.infradead.org, Pavel Machek , Ulf Hansson , Richard Weinberger , Artem Bityutskiy , Adrian Hunter , Jan Kara , Andreas Herrmann , Mel Gorman , Chunyan Zhang , linux-kernel , 'Paolo Valente' via bfq-iosched , Mark Brown Date: Wed, 03 Oct 2018 09:00:46 -0700 In-Reply-To: <6AF8CEDE-2720-4206-900A-1A9B914A8FF0@linaro.org> References: <20181002124329.21248-1-linus.walleij@linaro.org> <05fdbe23-ec01-895f-e67e-abff85c1ece2@kernel.dk> <1eca41df95ff660eb247a3de666adeb4@natalenko.name> <6AF8CEDE-2720-4206-900A-1A9B914A8FF0@linaro.org> Content-Type: text/plain; charset="UTF-7" X-Mailer: Evolution 3.26.2-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2018-10-03 at 17:55 +-0200, Paolo Valente wrote: +AD4 The problem, in particular, is that bfq is a complex beast, fighting +AD4 against a jungle of I/O issues. You have to be really into bfq, even +AD4 to just know all of its features+ACE This is a problem by itself. I don't know anyone who wants to have to deal with I/O scheduler tunables. Bart.