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[66.29.164.166]) by smtp.gmail.com with ESMTPSA id t7sm10699361pfh.101.2019.07.16.07.11.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Jul 2019 07:11:51 -0700 (PDT) Subject: Re: [PATCH BUGFIX IMPROVEMENT V2 0/1] block, bfq: eliminate latency regression with fast drives To: Paolo Valente Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, ulf.hansson@linaro.org, linus.walleij@linaro.org, bfq-iosched@googlegroups.com, oleksandr@natalenko.name References: <20190715105719.20353-1-paolo.valente@linaro.org> From: Jens Axboe Message-ID: <6867cf11-d7f8-cadf-b9ec-85549bb86af3@kernel.dk> Date: Tue, 16 Jul 2019 08:11:49 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190715105719.20353-1-paolo.valente@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/15/19 4:57 AM, Paolo Valente wrote: > [V2 that should apply cleanly on current HEAD] > > Hi Jens, > I've spotted a regression on a fast SSD: a loss of I/O-latency control > with interactive tasks (such as the application start up I usually > test). Details in the commit. > > I do hope that, after proper review, this commit makes it for 5.3. If it's a regression, it should have a Fixes: line telling us which commit originally introduced the regression. This is important for folks doing backports. Can you add that? -- Jens Axboe