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[80.230.68.31]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-47aa039b126sm32286020f8f.24.2026.07.07.03.25.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Jul 2026 03:25:40 -0700 (PDT) Date: Tue, 7 Jul 2026 06:25:36 -0400 From: "Michael S. Tsirkin" To: "David Hildenbrand (Arm)" Cc: Sourav Panda , muchun.song@linux.dev, osalvador@suse.de, akpm@linux-foundation.org, ljs@kernel.org, liam@infradead.org, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, mhklinux@outlook.com, fvdl@google.com, gthelen@google.com, mike.kravetz@oracle.com, pasha.tatashin@soleen.com, rientjes@google.com, riel@surriel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [RFC PATCH 0/6] mm/hugetlb: Dynamic, NUMA-aware HugePage Cache & Free Page Reporting Message-ID: <20260707062428-mutt-send-email-mst@kernel.org> References: <20260707064235.1386552-1-souravpanda@google.com> <9624988a-366e-4884-9408-3f3b88c27290@kernel.org> MIME-Version: 1.0 In-Reply-To: <9624988a-366e-4884-9408-3f3b88c27290@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 4RoeKMfu3ds6d6kG5Os3JvvX66jKpWHZ87Ei-EvwTy0_1783419941 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 34FE7C0002 X-Stat-Signature: 4gzx7fxff1q6ttau9s35n6rd1qqoe5i6 X-HE-Tag: 1783419946-315898 X-HE-Meta: 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 WkJBkq8O ArK0adTWTH/3cnQHnP4rqgQ/r6Nx2UaZIjNguqlFPuOJzxW6j//cGJCj6W+U8TOtzBaY2+4APEDAkLG9hrJMVTEttzPlC1JFFLRvuxafxcQczFw8Oh8N1RYiiIj88WI93L3PME1uIm6/wIzQmd/J9mosxcJqBsEG4jkIzLpqr6+kUUCsh21XP3F6+aHZWNiDcLWCMug21hTBf/ZvN1B/TREo4Dw38hW+i0k3JoPEV6hXAbsBBffFZQCL06mRn5c5HBjGtTuOqEagWHylL0T43CGE3sx9WvFoQBZhageaMKLQrI81n7RjudkRsqqDHkI9OivFuOTha8v23NB4= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jul 07, 2026 at 09:29:07AM +0200, David Hildenbrand (Arm) wrote: > On 7/7/26 08:42, Sourav Panda wrote: > > Overview > > This patch series introduces a dynamic, NUMA-aware HugePage Cache, > > backed by a kernel shrinker to safely return memory under pressure, and > > integrates it with Free Page Reporting (virtio-balloon) for HugeTLB, > > specifically targeting gigantic (1GB) hugepages. The goal is to solve > > the tradeoff between allocation latency and memory > > fungibility in virtualized and heterogeneous cloud environments. > > Hi, > > in general, we consider hugetlb nowadays to be mostly in feature freeze, as we > realized a while ago that adding more special casing on top of something too > special for all of MM is only going to hurt us more in the long run. > > We want to have less special casing and less special sauce, not more. > > Now, there is nothing wrong in making hugetlb be less special, by making it use > more of core infrastructure etc. > > But optimizing for surplus hugetlb pages by teaching hugetlb about new caches > and its custom free-page-reporting support rather looks like the wrong direction > for me? > > -- > Cheers, > > David It is currently bypassing free-page-reporting completely. Making existing free lists not ignore free-page-reporting would maybe considered "making it be less special"?