From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f44.google.com (mail-ed1-f44.google.com [209.85.208.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6777E2E6CC8 for ; Thu, 11 Jun 2026 09:23:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781169798; cv=none; b=Mp5Aqa/U9R0xUnILZ0BnxlbTbYpy7b1/UicjeXrz2tIlEFXR16hrV3z2FFGv95tao+3TS8HA+TKUytKlpTOpbdO+1vaKAen2cttKzwj+ao/9KNpbxzNQVcDJeqYfq2U03OH54YmQVYyyX6zGUyF7T+BNQ0WdylH5w1f1wO+d7cg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781169798; c=relaxed/simple; bh=lOt+x/scnE6ZFrVz5Kyx1thrHH0tT9/TOT2ikoIMsAA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=emsxHDABcLJqVvR46ynGTa4Kj5QiMMdFh7T+wug+4Rbu2ZrLuG8k0PyJT80tXah8DCxvduudN/FpsTHTSE2shkLWyhqgEYCR74wjAEZI3rKxcJtvpEz8MhQLCd/fZ54RHOqblo1mMqvKcUbEotkU6bwTkceek0ty6v37PB0hBRs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=AOjyBS/g; arc=none smtp.client-ip=209.85.208.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="AOjyBS/g" Received: by mail-ed1-f44.google.com with SMTP id 4fb4d7f45d1cf-6924a68e3f3so4959399a12.1 for ; Thu, 11 Jun 2026 02:23:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1781169796; x=1781774596; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=7UWn+/o1z8vjqgLMtj+iGKcEAIf/D00Y5lREVjVXChc=; b=AOjyBS/gUWgy4GtA0ONFqF5y5P5zy/gcv8Vq/5/v/cEi5NqfbCC2PJFcX4I/hugsII +rCF4hOAFRhjJRfNSdAarfYm9dMQ8EWGWr2NFowUwLaL8+Lay2AGizFgrOSdiIOrk0e6 ZduN7BWQCWuuHkNxKUcQ480aZ8FjnXkwV/yUXNBxBbP9Nb9mECbdxylbSlC24cVbvvXa YG5HulAnYzNRhgeeeWj1r1baMjuF0TGnuPa6S6LM7acUC/fr1ej1rPwF5Y/pctW1GMFA KZk1ShwuEEDHsjvqzOHUy01givXUelOiUnYWDME7t12SMsLCgxuQH49o6BZAnk2zdQEY 7euA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781169796; x=1781774596; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=7UWn+/o1z8vjqgLMtj+iGKcEAIf/D00Y5lREVjVXChc=; b=PcNqS9wS9/zsSOTzJ8TpDw+e+24tebhjeYivmPYZ8EEisM43jUQPpIJROrt5TKmX7+ o9x2Psct/YdGO+DktwJ126NVZt2VDHh15I/RrAc1+pfG9sAfHR1Gb1w7PgkwYmt9LbPQ 8qsd9gVH/mXKNbbtxS8376g7HTcpI0W/9DwYcniKDfksZcP3Km4iPFL3nwljLUOq84Uu gJ41oWzvC6jNFSFQBf8mgRXexLDnpdHmdgH6FDmE0FH8tck9EuGTFWovoyIBe5x+Q74w O4G8KdO7R2jua0fuU3kuuJkjVC9abfDBGUOHB7vuHv5x1VWo56uQOIOZwzS1USo/FRgH Ll8Q== X-Forwarded-Encrypted: i=1; AFNElJ9ndGJg4D1qodhOY0pNOiKPOGXAz4PwfobAZyh0OTtuO+d0LEWDypfdhsnfwecp4w3QHdXHCQmW4D8kMvI=@vger.kernel.org X-Gm-Message-State: AOJu0YyFhdzgrmTKgQBBBd78uIka3LrXJYtm3IRFsbqsBx/dBQPMXnHP r8hieAocQMa6/lzQ1J5secAH2T5b7Qz0Lz+cIyq4RAqsA24Kipx9m6hb X-Gm-Gg: Acq92OFvqiEsCctAg/U9q1FoAOeM5frkIHzl9QG36qas9pVowslcOaxcDM/24aWgSGR yES1s2dkGtxxiYfDV62x4Br2CNHK5PCCe9pp8u4hth8wTyp3LFuh3P7b8B7lDtD0shgxc2TvLb1 CRT5WdfBqKKsyLMtgzIV7KUQXVn7uHmnPusldq0dMt2nRDrKr9kvHoBSGIjLG/2SGo6tHX5ZokN hhH4xdH0A04T9npqwfwdhd+B4/CZycVqUSgV7i8pJWn1slNJfokP+goNSnL6l+jmk6cFhN2aBHw M9H24DQxpzp0lnz1BpNKqXVa4vmUHs0ZYKecl7co30BNUNp72FtkPzrJLwlo15yJ9hXF4ntiUeN dXBkD7d+I+qicagrTIf2mlme8hNLYv1tIeyVa79xLTby6sKsKatASgOD62eRdw5oWiQhma1orhW D8cC+O5KQ5kVyva6EGOCUstPlUIuLz1lKQ2R3eT1HeiaGkaBtwCOLXr69cS/YGeVx0llS73GSf9 ewxoYX2Ujz5XHWK7AcPMzvvt/IuSPcL6xo= X-Received: by 2002:a17:907:d048:b0:bfa:6dc1:3c64 with SMTP id a640c23a62f3a-bfc85c82bbbmr78034866b.13.1781169795458; Thu, 11 Jun 2026 02:23:15 -0700 (PDT) Received: from localhost (pat-125-253.wlan.net.ed.ac.uk. [192.41.125.253]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-bfcb53ca055sm36691266b.38.2026.06.11.02.23.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Jun 2026 02:23:14 -0700 (PDT) Date: Thu, 11 Jun 2026 10:23:13 +0100 From: Karim Manaouil To: Lorenzo Stoakes Cc: Nico Pache , Luka Bai , David Hildenbrand , David Rientjes , linux-mm@kvack.org, Andrew Morton , Zi Yan , Baolin Wang , "Liam R. Howlett" , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kairui Song , Qi Zheng , Shakeel Butt , Axel Rasmussen , Yuanchu Xie , Wei Xu , Rik van Riel , Harry Yoo , Jann Horn , Johannes Weiner , linux-kernel@vger.kernel.org, Luka Bai Subject: Re: [PATCH 0/5] mm/khugepaged: add collapse hint machanism for khugepaged and use in mglru Message-ID: <20260611092313.7d4knb2irt2rtswu@wrangler> References: <20260531-thp_collapse_hint-v1-0-866339cd4c2a@tencent.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jun 09, 2026 at 03:44:21PM +0100, Lorenzo Stoakes wrote: > On Tue, Jun 09, 2026 at 04:17:45AM -0600, Nico Pache wrote: > > I had future plans for something similar as part of the thp=auto work; > > however that requires significant thought and investigation into how > > we can properly gather hints for collapse/split THP candidates. From > > my perspective we'd want a more global structure/system outside of > > khugepaged, that would directly call khugepaged (and others like > > split, etc). It would also tie into the allocator so that at fault > > time it could leverage the hints to make better decisions. My fear > > with this series is that making a decision now might complicate future > > work by adding complexity we may eventually want to remove for a > > better solution. > > I know this is future planning stuff, but I want to point out that we need > to see significant rework of the THP code base before accepting any further > major changes. > > > > > If you have the chance perhaps you can lead a discussion on your > > proposal at the biweekly MM alignment session. > > > > +David Rientjes as he leads those discussions. We could use that time > > to layout a plan for what needs to be done for this work, and for the > > work surrounding thp=auto as I beleive they will be interdependent :) > > We prefer to discuss THP topics in the THP cabal meeting, which both THP > maintainers regularly attend :) having separate sessions we might not be aware > of isn't really helpful. Hi Lorenzo, How to participate in the THP cabal meetings? Is there any public link to join? I'm working recently on anti-fragmentation, which is kind of relevant... Thanks > And 'THP auto' is a broad topic rather than a new feature. I don't think it > should be seen as a topic 'owned' by anybody, but rather something that we > as a community should discuss. > > Series that appear from nowhere trying to implement significant changes > along those lines without community disucssion will not be hugely > appreciated :) > > Thanks, Lorenzo -- ~karim