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([2601:647:4802:9070:be97:ffd:339d:919c]) by smtp.gmail.com with ESMTPSA id a84sm10727208pfa.53.2020.11.13.13.36.17 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 13 Nov 2020 13:36:18 -0800 (PST) Subject: Re: [PATCH] iosched: Add i10 I/O Scheduler To: Jens Axboe , Rachit Agarwal , Christoph Hellwig References: <20201112140752.1554-1-rach4x0r@gmail.com> <5a954c4e-aa84-834d-7d04-0ce3545d45c9@kernel.dk> <10993ce4-7048-a369-ea44-adf445acfca7@grimberg.me> From: Sagi Grimberg Message-ID: Date: Fri, 13 Nov 2020 13:36:16 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201113_163620_787360_779775AF X-CRM114-Status: GOOD ( 16.38 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Qizhe Cai , Rachit Agarwal , linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, Ming Lei , linux-block@vger.kernel.org, Midhul Vuppalapati , Jaehyun Hwang , Rachit Agarwal , Keith Busch , Sagi Grimberg Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org >> But if you think this has a better home, I'm assuming that the guys >> will be open to that. > > Also see the reply from Ming. It's a balancing act - don't want to add > extra overhead to the core, but also don't want to carry an extra > scheduler if the main change is really just variable dispatch batching. > And since we already have a notion of that, seems worthwhile to explore > that venue. I agree, The main difference is that this balancing is not driven from device resource pressure, but rather from an assumption of device specific optimization (and also with a specific optimization target), hence a scheduler a user would need to opt-in seemed like a good compromise. But maybe Ming has some good ideas on a different way to add it.. _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme