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b=iKE/XKppWbSzjEt/knKYntQMNUjU3xxyGzG/qqWR+NjqD77xwNrloFoFmpEUo0H42 roqpGnzg/ZLZSqyjVveOpTZCbABjNrSjLZSWz7qyeQNTfHZT+bzmgpID1DYDQ/kCtX aehIQzFzOxyaKZX8vE86cvy1wKe8GVf2THmdarEShk9FErMaLsEroyi1y7nSTrZGkM mTb6qKQSPEah//6s9yXgPifJZ9QYU7LkeavHkqOkGj1b8M2cOMO5TmoUkoyR0pt++p wiPnM9goFqsFH7vGYwOKMYLBeb1N6bnbPenlz7dGCKZxumg8CeTDclFwx39Bk33cAp 16Ex83MlBaJiA== From: SJ Park To: Gutierrez Asier Cc: SJ Park , Lian Wang , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v4 1/3] mm/damon: Introduce DAMOS_QUOTA_HUGEPAGE auto tuning Date: Wed, 2 Sep 2026 08:15:48 -0700 Message-ID: <20260902151548.88735-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <9ac2a10f-1551-410e-a9c0-173a1daeb1ab@huawei-partners.com> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: tm6g3gxkg45xkpwf6mq5u75i5wsz19ni X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 9C39AC000B X-Rspam-User: X-HE-Tag: 1788362156-642630 X-HE-Meta: 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 iNwdI/1P 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, 2 Sep 2026 18:03:39 +0300 Gutierrez Asier wrote: > Hi SJ and Lian, > > On 9/1/2026 5:23 PM, SJ Park wrote: > > Hi Lian, > > > > On Tue, 1 Sep 2026 14:58:35 +0800 Lian Wang wrote: > > [...] > >> Second, the metric is global while a DAMOS scheme can target one process. > > > > Actually it can target multiple processes if those are in single DAMON context. > > > >> THPs from other processes or NUMA nodes can satisfy the target or dilute the > >> monitored process's changes. Is this intentional? > > > > I think it is intentional. The user should have the control on collapsing > > hugepages, or believe the uncontrolled collapse mechanisms. > > > >> If so, documenting the > >> scope and testing a background THP workload may be useful. > > > > More documentation and testing are always welcome :) > > > >> > >> The temporal results approach the 10% and 25% targets, while the consistent > >> results overshoot the 10% target to about 20% and 45%. I would describe this > >> as control-response data. TPS, latency, TLB, fragmentation and collapse CPU > >> data could further show the workload benefit and cost. > > > > Yes, those would be helpful. That's not mandatory for this simple change in my > > opinion, though. I would let Asier decide whether and when to make and share > > such data. > The idea of this patch was to introduce auto tuning. I think I submitted thebenchmark results when I sent the DAMOS_COLLAPSE feature. > > Anyway, it shouldn't take long for me to get more data. I think it may be useful > for people to know the actual results in real application. > > SJ, what's the best place to publish all those data? I believe you have more > experience sharing this data and which platform is the most useful one.>> I'm never an expert in visibility :) But if I should recommend, I get three places off the top of my head. First, you could simply share the data with plain mail on DAMON and wider kernel mailing lists like linux-mm@ and linux-kernel@. Second, if the data is matured, sharing those in conferences like LPC, OSSummit, FOSDEM or DAMON (nano) Conference would be nice. Third, if you prefer text, LWN or personal blogs like medias could also be good places. I also maintain DAMON porject blog [1]. Kunwu and Lian actually contributed an article to the blog before. If you want to submit an article there, let me know. [1] https://damonitor.github.io/posts/ [2] https://damonitor.github.io/posts/tlb_flush_policy/ Thanks, SJ [...]