From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 366C441C313; Fri, 22 May 2026 14:05:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779458710; cv=none; b=BHwNaqUrv3zpEG0+dChKO/GCZeE24Az1uWFZpArHq4LDOyXbipc/xiZVOv0yEul3nHwlW35Fyhl601JrifunO1H/HOkAzsP0vhs+Atriv1pzmQEPCTtRX1zJ0fSHU3BJuldWZfz/hnHBzPEsBr655nVjUhY6FT5bcwwxO/Xs8qg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779458710; c=relaxed/simple; bh=2UZjwiT2X1cW7AhTepmwlyEVOZvzDO0GFHHZ7F3hu2k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Zp7LQzxyXcvBWxx8f7fZ26XMoIMFbsTCcFgvfv0yvxOoS1jzvwh/lqaGvDXLpFs5/AsqTn5Iym+B4el+0OS0Fs1YBytl6Y7diudd0z1+tZiKBGpH+TD5N1oQ/QgiTcs1zYRwV9Sq/vkKA7KQ6qzLfp0yRDI8qcFZ6jLRNg/+Hxw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mxNBYUYp; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mxNBYUYp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 490CD1F000E9; Fri, 22 May 2026 14:05:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779458701; bh=6Ie8d2ZAmeBfN3v2/FX4Pbrv/H8u5AdvngzMgJa2Mf8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=mxNBYUYpnAWw8vEEAYBoOy4sKcHYDEtI47yZ4w+/tWMhgmVlXSO42ghF4ocDrA/Aa qEOD7hdtIQYl+6j50auuLdIOl4bUcsbtT55PmICGuXR7SyMh2ebncRH9j18harNy5s qlg/hCMCHbwEcgsALFwbKABqFNiMuxZd3EMh9xh0gVby+C5KXSKR84QkV32rnI8LT2 0bJ3nVYCp8E/zU5w0An8h/WG1g338+A/m44oNUI74RvF777xYt+qVpBF6hWgaauV0t 7bt0Lz1+iQNY/540jiITxZLdfliZjCalbs6kr6IUzf0TtDKSgYbup6xFpsqphGMUf0 SoRh5hhyPT4Fw== Date: Fri, 22 May 2026 14:04:59 +0000 From: Jaegeuk Kim To: Matthew Wilcox Cc: Theodore Tso , linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Christoph Hellwig , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Akilesh Kailash , Christian Brauner Subject: Re: [f2fs-dev] [PATCH v2] f2fs: another way to set large folio by remembering inode number Message-ID: References: <20260409134538.3692605-1-jaegeuk@kernel.org> <20260521155748.GA79343@macsyma-wired.lan> 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 05/22, Matthew Wilcox wrote: > On Fri, May 22, 2026 at 03:59:45AM +0000, Jaegeuk Kim wrote: > > On 05/21, Matthew Wilcox wrote: > > > On Thu, May 21, 2026 at 11:57:48AM -0400, Theodore Tso wrote: > > > > So let me get this straight. This is a magic xattr interface which is > > > > not even persisted in the file system, but instead sets a 32-bit > > > > bitmask in the struct inode which disappears once the inode gets > > > > flushed from the inode stack. And it uses a generic xattr name, > > > > "user.fadvise". > > > > > > > > There's no way in *hell* any other file system is likely to adopt such > > > > a broken interface, so why didn't you just use an ioctl to set this > > > > magic f2fs-specific flag? > > > > > > I mean, yes, this API is horrendous. But it's just another example of > > > f2fs thinking it's somehow special and not just enabling large folios > > > like other filesystems do. This hurts everyone, not just people who use > > > f2fs. > > > > >From the production viewpoint, I raised a concern on setting large folio by > > default, since that exhausts lots of high-order pages, which were needed for > > essential system services and critical apps. > > Random fears or actual data? This was a quick buddyinfo right after booting the device. Before: Node 0, zone Normal 22684 42284 28704 16901 9515 4566 1854 673 181 36 758 After disabling EROFS large folio: Node 0, zone Normal 8486 4732 2175 1161 697 272 82 19 3 1 856 > > > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel