From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75D87435AB7 for ; Tue, 28 Jul 2026 18:24:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785263099; cv=none; b=aS8OJK2OsD4Xinl3YVUt6IqggWol8PqqjU6IYS5v/JrvLs0EpJ39dhM2H1tu8ayBZ/nAF1auC2PGQVlJt3lho3/L48QSK9kbnLip+Ro2bmhzNOpbMxAr6M4SbWqG9Mmq47NRcF3ypNfZ2O0qIn3On81jNlj4YbAfIFU7QHJWitk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785263099; c=relaxed/simple; bh=EXvAMvySo1cWp4sVtYUUk2z1dPNCQ71rghUUBsNp/uo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DboPU9LI1X0vf1sXvTdNZ2hUbKlVsQ8bnmVUz+0K/sGvyJXSc5x/OHFaLkfqCTmZb2emmYVuJsht1E6bxMlSpcq8cpE1Y2Pm93kceXUIQkX4Vs96GG5k2rTABmEX9AOqUzYxDMM3jDJyobvmTU+qeAXSzYqnHIJBENhCQbOz1bE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=pass smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=gAQV/3zD; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gAQV/3zD" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jP8z/RaADyj4SpOiJr76y895B8w3LXU0vC4QQdU3dfg=; b=gAQV/3zDg05LuH2uSK40ydF48M PmFT2ztWssSY9W16jKElvZf5r2T432m+Qnq3DvMveYg4dmdBjwii/MrvFRNQsK6Vi68KO4GoIHyWv SK77RTvJBOxzzYyujqP1XnrJ2t9lFQoNr0HSYX90ca7hMJLjjcuFNFS6Qsu2FA0jlDpY3oNAMrtD5 SH/WZbvWa53EqknNeEBvC8yS/KAidOEuXunmUjSC4EQdvaPqBqsFXobAMduJC7P25pg2GYNd8TrhE wGMfC7WvSUwJa4rxXHdaiAecf1TSeZRj5dFfP+ICKJ0fa/Xrfu+vvR5WQnqeOE/3s2L9RrsE53JQZ CQB488Gw==; Received: from willy by casper.infradead.org with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1womTu-0000000DxDa-0uJx; Tue, 28 Jul 2026 18:24:46 +0000 Date: Tue, 28 Jul 2026 19:24:46 +0100 From: Matthew Wilcox To: Andrew Morton Cc: Bharata B Rao , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Jonathan.Cameron@huawei.com, dave.hansen@intel.com, gourry@gourry.net, mgorman@techsingularity.net, mingo@redhat.com, peterz@infradead.org, raghavendra.kt@amd.com, riel@surriel.com, rientjes@google.com, sj@kernel.org, weixugc@google.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, dave@stgolabs.net, nifan.cxl@gmail.com, xuezhengchu@huawei.com, yiannis@zptcorp.com, david@kernel.org, byungchul@sk.com, kinseyho@google.com, joshua.hahnjy@gmail.com, yuanchu@google.com, balbirs@nvidia.com, alok.rathore@samsung.com, shivankg@amd.com, donettom@linux.ibm.com Subject: Re: [PATCH v8 0/8] mm: Hot page tracking and promotion infrastructure Message-ID: References: <20260728054356.291998-1-bharata@amd.com> <20260728111401.b6d674baf8e56a27c55e0c52@linux-foundation.org> 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: <20260728111401.b6d674baf8e56a27c55e0c52@linux-foundation.org> On Tue, Jul 28, 2026 at 11:14:01AM -0700, Andrew Morton wrote: > On Tue, 28 Jul 2026 11:13:48 +0530 Bharata B Rao wrote: > > > This patchset introduces pghot, a subsystem for hot page tracking and > > promotion. > > Can DAMON be used to do this sort of thing adequately? > > Thanks, I'll await review input on this. I don't think we should do this. I don't think it's a use-case that customers actually want; I think it's something CPU vendors think their customers want. I've said this repeatedly over the months this patchset has been in development. I say no.