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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , "Matthew Wilcox (Oracle)" , Stephen Rothwell , open list , "open list:MEMORY MANAGEMENT - MISC" , "open list:PAGE CACHE" Cc: anuj20.g@samsung.com, hch@lst.de, bernd@bsbernd.com, djwong@kernel.org, jack@suse.cz, opensource.kernel@vivo.com From: Kundan Kumar In-Reply-To: <20250825122931.13037-1-wangyufei@vivo.com> Content-Transfer-Encoding: 7bit X-CMS-MailID: 20250829090001epcas5p1624018975802eceeb655e76bf63d152a X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" CMS-TYPE: 105P cpgsPolicy: CPGSC10-542,Y X-CFilter-Loop: Reflected X-CMS-RootMailID: 20250825123009epcas5p1573496e2cad2f58d22036493e5af03be References: <20250825122931.13037-1-wangyufei@vivo.com> X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 613894000E X-Stat-Signature: qijtqgw7n6qjooip87sfqatyoa7bohuz X-Rspam-User: X-HE-Tag: 1756458007-323080 X-HE-Meta: U2FsdGVkX1+9DDu+Z5fTkcEIGdlIR0420b33fv/OuO1IVrYUmx//+vIuU48qa2oJ/7Czv/PHIhQq8V37ZYiKW72UeS5+wmJOT9PJVnY+bzfJOGMNKXMM7iB3Vdz3KbEMnnNEHA6uQtGDpF5drxaIsdOzRWEFKEWf98HtdkvpuX31CNi2w2WjCdVZ9AVwVMtkdaDGKBPN+Nt6HH4bO5bQVbhKwmyf6BSvBnoOc43nvx/QUOtGTUx0+HKmkRNb0uRG4y66BFxVmISu2zwhdfulLMm6vumLuA57N+X7BfsrKmyDxevQMTY7fPz/jHYoZV2zqmgTtmlHMOoHIPX4xgEXlLS4bxQvIknlLDlVp1O7npTOCZDG03QI/OuASNbplkoY1n54OOeXZXe7kp0RzUGiaxLdQOJp+iWwjLj0rh6dpMtzdi1PLD+3L7T3h45dJLMJ2rYvrju34BHP8g87fF/y1CTp9dxK8kdLARK3mWe6pgCI4kLlXVsUK3cLBIL/RyO6jjvQppA5vAkx1Um4vifPGSFUfUsSuRVfi7snhVXGQDDHthfeYYeCQjYixY9P5cg+O3UfbTwve5UpwWdYVaPu6BkMziAo2/+gELGD1xJUunHAqAPiddwDD+FvBrsQiGZusAIQkLWDqN0AMB3/kiwzY1jVBv4sTXGW3+4QnrhB0TElAXRVUx5bJRALLAEsoyQ2SgcCDxK0lPdxxOKgBYkLjKrLH3iiG2A5DUyprJW6haA8CctQb/1q1DzMuzuWp2A1neAme0djQYrPBqac6vhTkgdvhpMNMDWUG1uNhqZxq6REQ/ShPbSkIQYOYVGSGVqYhItkw4vEPj5lxf6PQWS2+saNIRCADRHw3+P2rwnSeR2elX3wBCESjbZkRacG4StHLxVJ3ZyHXdsUWjj3i0uwsoxPqwF2NDt7gci/KObs0qtBOvY5SC4/aP5wTs8HvkGXX7mTVWyH/plevu4fN/d 3DvBwQmy pt51/X/QhHytJ0x12Va5xgQdkeS3T8E8SzBKV X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 8/25/2025 5:59 PM, wangyufei wrote: > Hi everyone, > > We've been interested in this patch about parallelizing writeback [1] > and have been following its discussion and development. Our testing in > several application scenarios on mobile devices has shown significant > performance improvements. > Hi, Thanks for sharing this work. Could you clarify a few details about your test setup? - Which filesystem did you run these experiments on? - What were the specifics of the workload (number of threads, block size, I/O size)? - If you are using fio, can you please share the fio command. - How much RAM was available on the test system? - Can you share the performance improvement numbers you observed? That would help in understanding the impact of parallel writeback? I made similar modifications to dynamically configure the number of writeback threads in this experimental patch. Refer to patches 14 and 15: https://lore.kernel.org/all/20250807045706.2848-1-kundan.kumar@samsung.com/ The key difference is that this change also enables a reduction in the number of writeback threads. Thanks, Kundan >