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[146.241.85.178]) by smtp.gmail.com with ESMTPSA id a64sm26629527wmf.1.2019.07.18.00.09.05 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 18 Jul 2019 00:09:06 -0700 (PDT) From: Paolo Valente To: Jens Axboe 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, bottura.nicola95@gmail.com, srivatsa@csail.mit.edu, Paolo Valente Subject: [PATCH BUGFIX IMPROVEMENT V3 0/1] block, bfq: eliminate latency regression with fast drives Date: Thu, 18 Jul 2019 09:08:51 +0200 Message-Id: <20190718070852.34568-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [V3 that mentions the fixed/improved commit] 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. Thanks, Paolo Paolo Valente (1): block, bfq: check also in-flight I/O in dispatch plugging block/bfq-iosched.c | 67 +++++++++++++++++++++++++++++---------------- 1 file changed, 43 insertions(+), 24 deletions(-) -- 2.20.1