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[35.169.212.159]) by smtp.gmail.com with ESMTPSA id t64sm4470921qkd.71.2021.08.06.04.48.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Aug 2021 04:48:07 -0700 (PDT) From: SeongJae Park X-Google-Original-From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , Shakeel Butt , SeongJae Park , Jonathan.Cameron@huawei.com, amit@kernel.org, Jonathan Corbet , David Hildenbrand , dwmw@amazon.com, foersleo@amazon.de, Greg Thelen , jgowans@amazon.com, mheyne@amazon.de, David Rientjes , sieberf@amazon.com, Vlastimil Babka , linux-damon@amazon.com, Linux MM , linux-doc@vger.kernel.org, LKML , Wei Xu , Paul Turner , Yu Zhao , Dave Hansen Subject: Re: [PATCH v34 00/13] Introduce Data Access MONitor (DAMON) Date: Fri, 6 Aug 2021 11:48:01 +0000 Message-Id: <20210806114801.6958-1-sjpark@amazon.de> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210805170344.afbf5f1ceb00eb212082ca7b@linux-foundation.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: SeongJae Park On Thu, 5 Aug 2021 17:03:44 -0700 Andrew Morton wrote: > On Wed, 28 Jul 2021 08:36:43 +0000 SeongJae Park wrote: > > > > DAMON does not expose stable APIs at the moment, so these can > > > be changed later if needed. I think it is ok to merge DAMON for some > > > exposure. However I do want to make this clear that the solution space > > > is not complete. The solution of system level monitoring is still > > > needed which can be a future extension to DAMON or more generalized > > > Multigen LRU. > > > > Agreed. We have lots more works to do. Some of those are already posted as > > RFC patchsets[1,2,3,4]. I promise I will happily do the works. But, how dare > > could only I get all the fun? I'd like to do that together with others in this > > great community. One major purpose of this patchset is thus providing a > > flexible framework for such collaboration. The virtual address space > > monitoring, which this patchset provides in addition to the framework, is also > > for real-world usages, though. > > > > Now all the patches have at least one 'Reviewed-by:' or 'Acked-by:' tags. We > > didn't find serious problems since v26[5], which was posted about four months > > ago. so I'm thinking this patchset has passed the minimum qualification. If > > you think there are more things to be done before this patchset is merged in > > the -mm tree or mainline, please let me know. If not, Andrew, I'd like you to > > consider merging this patchset into '-mm' tree. > > Shall take a look. With some trepidation. > > 1-2 years from now someone will pop up with a massive patchset > implementing some monitoring scheme and we'll say "why didn't you use > DAMON" and they'll say "it's unsuitable for ". Agreed. And I personally believe merging this in will help avoiding such situation, because the someone will be able to easily find the developer who is responsible to convince the person. I will happily and definitely do my best for that. > > I would like to see more thought/design go into how DAMON could be > modified to address Shakeel's other three requirements. At least to > the point where we can confidently say "yes, we will be able to do > this". Are you able to drive this discussion along please? Sure. I will describe my plan for convincing Shakeel's usages in detail as a reply to this mail. Thanks, SeongJae Park