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 637491E480 for ; Sun, 23 Feb 2025 12:47:59 +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=1740314881; cv=none; b=fSaL8RQ63QgGS/i0kLiGtJXU+VoBEA93H+iu4x4j7Gvd2ubEsvH+ytCtjiyOjWNy7eWoheVdtjj1rMoC0ofJrFq99/Itq7+GVLj7ul97WpcKvd92mJLNPJGE1iUPT3ADw2PWS37WPmG2YJ+9GQXAU8ocImOd094ehUoP0tDTB5U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740314881; c=relaxed/simple; bh=xuZP8v71qbCGLPCF+bW6uiv6JpAfZnjI5UZrdEdAqPc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=a5sLNX06lp9G1E2qvoO5gNsKluZmKUEswiHppBfch2qsaGXuEKyzDEZQLGTfvRXqs7NiESiubxIrGaE60iYh/zjr7RNx5wJIGVobUTOLAafBn1SyIgCNcc+nMjQjFjaFhsvTtVZPlbUiYFt9W6MsR+AFUVpjasrkQuNwCrE5Ycg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=gRjDaoFo; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none 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="gRjDaoFo" 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=xuZP8v71qbCGLPCF+bW6uiv6JpAfZnjI5UZrdEdAqPc=; b=gRjDaoFoyxczkCC628NDdHgA9a YncFRWrnB4o81jjOtXet0uLPz0qUl2hCwhWE4Cvcs9oVdet/kUAcOU7P6KpFEzEgmM8+yLTcv03to IG6wVRSRL60lsgZdpENmMP4Oec4CETschP3c7cRZej6oOLLr6+i87rFR9W/wJugqWBex6KeM6qb7F 6Awctw2++Gl4bjUzK2IZWWKPV8UG/1cmFXfkN+HqkGa3xIb4uCn1KnAVwbwhK6TApBHfM+CC0gs8n M2rAcNVMVLbc9e46ptbKKSfYmdH4pvwTX1VkbrPLkP1I1nyuykUpAkjwgoagOaavWd064VoJ/ZZrX X2JunpiA==; Received: from willy by casper.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tmB2Q-00000003W7i-0ZCT; Sun, 23 Feb 2025 12:24:50 +0000 Date: Sun, 23 Feb 2025 12:24:49 +0000 From: Matthew Wilcox To: Lorenzo Stoakes Cc: Kalesh Singh , Kent Overstreet , lsf-pc@lists.linux-foundation.org, "open list:MEMORY MANAGEMENT" , linux-fsdevel , Suren Baghdasaryan , David Hildenbrand , "Liam R. Howlett" , Juan Yescas , android-mm , Vlastimil Babka , Michal Hocko , Johannes Weiner , Nhat Pham Subject: Re: [LSF/MM/BPF TOPIC] Optimizing Page Cache Readahead Behavior Message-ID: References: <31e946de-b8d5-4681-b2ac-006360895a87@lucifer.local> Precedence: bulk X-Mailing-List: linux-fsdevel@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: <31e946de-b8d5-4681-b2ac-006360895a87@lucifer.local> On Sun, Feb 23, 2025 at 09:30:57AM +0000, Lorenzo Stoakes wrote: > It seems strange to me sparse regions would place duplicate zeroed pages in > the page cache... https://lore.kernel.org/linux-mm/Z7p-SLdiyQCknetc@casper.infradead.org/