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[146.241.5.103]) by smtp.gmail.com with ESMTPSA id o3-v6sm30036180wrj.31.2018.08.16.09.51.54 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 Aug 2018 09:51:55 -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, broonie@kernel.org, bfq-iosched@googlegroups.com, oleksandr@natalenko.name, Paolo Valente Subject: [PATCH BUGFIX/IMPROVEMENT 0/4] bfq: two fixes and one improvement related to I/O control Date: Thu, 16 Aug 2018 18:51:14 +0200 Message-Id: <20180816165118.17402-1-paolo.valente@linaro.org> X-Mailer: git-send-email 2.16.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jens, while working a little bit on cgroups I/O control, I found two nasty bugs in bfq. They break bandwidth control in simple configurations with one-process groups. These bugs are fixed by the first two patches in this series. These fixes improved I/O control so much, that I could reduce the write overcharge factor, used by bfq to counter write-induced issues. This reduction is performed by the third patch. The fourth patch contains a little code improvement I made in a function that has to do with I/O control. I hope we are still in time for 4.19. Thanks, Paolo Paolo Valente (4): block, bfq: readd missing reset of parent-entity service block, bfq: always update the budget of an entity when needed block, bfq: reduce write overcharge block, bfq: improve code of bfq_bfqq_charge_time block/bfq-iosched.c | 54 +++++++++++++++++++++++++++++++++++++++-------------- block/bfq-wf2q.c | 22 +++++++++++----------- 2 files changed, 51 insertions(+), 25 deletions(-) -- 2.16.1