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 2195F9450; Mon, 24 Mar 2025 15:02:46 +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=1742828569; cv=none; b=tjmAeh7KMYnnIE89lOpOm+xABms7l2alK4pMCWTwb30B88vdCuXRfGbdKu7dtqz9ic5eVogaqDi1N96I/AbmlMn6pd5N7ohftvHEEcI9xHxbsXBp5JSrHVCL8UIdGkyKpVnijF4JU3ZflK5Xp2phC5MYFLWi8vvBVxy9SE6zfXE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742828569; c=relaxed/simple; bh=yv61cHAJiH0JNvFm2SJMGEiqMHIGpIt9dw/H9oZc3ps=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=X2o19QtboQiC34501n9QYqzCm5KU0nabbygD4/wIfps9U9+xHta84NKD+sPJHkmwq9tTqHUOdz5lR3bcrfcJ1+MYkb44xvE16afw3PzlTgJi9YfL40QtZJFsrROQ9bDmtO4e/U4r0eyu5gqlzNZZ5hp+0hQNHilqlcm085e7Wcw= 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=FBUtQeBP; 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="FBUtQeBP" 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=35uXtVKGaER37nteavlftmrAz1omkXbLtRVHdTRcrGg=; b=FBUtQeBPskXqJVfpcbX/bRxJvQ U2UCMFZYdpfbptLlHKjGYxLU2B8/oQDhAPnh21t9yzMuEVHHDwfI1ONuI6/zAc0hjPr1f7m1TZtZO e2dBaQR4jEQWGFfU+py5gItU6l5FA0x5kChkEyVut1rJ9GQXTwqjj/3UsuDEMZyQIdEioE301qkJA HTV1KguSRIZ0g9ni6Lw5xaadMh2gnEAIsmQknuozj4ZbDD08+uHfbDcSY3Y5DFFVBtrG3sBRLvxMH 8FDNI2L8lziT8Qzs2L6EqViVNqEq99VAOspCmx48yoD+PJtOba1BhHVs5tnsdSeddHaa5CsiS3EY3 Z8eGSKnA==; Received: from willy by casper.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1twjJu-00000000odr-3Z0q; Mon, 24 Mar 2025 15:02:30 +0000 Date: Mon, 24 Mar 2025 15:02:30 +0000 From: Matthew Wilcox To: Bart Van Assche Cc: Luis Chamberlain , leon@kernel.org, hch@lst.de, kbusch@kernel.org, sagi@grimberg.me, axboe@kernel.dk, joro@8bytes.org, brauner@kernel.org, hare@suse.de, david@fromorbit.com, djwong@kernel.org, john.g.garry@oracle.com, ritesh.list@gmail.com, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-mm@kvack.org, gost.dev@samsung.com, p.raghav@samsung.com, da.gomez@samsung.com, kernel@pankajraghav.com Subject: Re: [RFC 2/4] blkdev: lift BLK_MAX_BLOCK_SIZE to page cache limit Message-ID: References: <20250320111328.2841690-1-mcgrof@kernel.org> <20250320111328.2841690-3-mcgrof@kernel.org> <5459e3e0-656c-4d94-82c7-3880608f9ac8@acm.org> 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: On Mon, Mar 24, 2025 at 06:58:26AM -0400, Bart Van Assche wrote: > If the goal is to reduce DRAM costs then I recommend SSD manufacturers > to implement zoned storage (ZNS) instead of only increasing the logical > block size. A big advantage of zoned storage is that the DRAM cost is > reduced significantly even if the block size is not increased. > > Are there any applications that benefit from a block size larger than > 64 KiB? If not, why to increase BLK_MAX_BLOCK_SIZE further? Do you agree > that this question should be answered in the patch description? Do I agree that we should use the commit message to enter into a philosophical debate about whether ZNS or large block sizes are better? No, I do not. I don't even think we should have this discussion any more on this mailing list; I think everyone is aware that both alternatives exist. You don't like it, and that's your prerogative. But at some point you have to stop being an awkward cuss about it. I think CXL is an abomination; I've made this point often enough that everybody is aware of it. I don't make it any more. All I do is NACK the inclusion of patches that are only for the benefit of CXL until CXL has actually demonstrated its utility.