From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 36E25313E0C for ; Mon, 1 Dec 2025 15:11:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764601885; cv=none; b=slMqimIqvzNMvsbXBE3uskZ8+OUPTxtGOKH9ubd+4LSYygwXTXKdNqdmmFl6hvK0zksOfMPW1R4J5PdijSb/z5vWCcE2JsvoZ49QovIiCpq2EBnBdwD8ih7XhxG84kkszcfA6Nhlzc89Jku7KxrXTEjtTcn54kXkuGJbavNwEV0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764601885; c=relaxed/simple; bh=CQjhTj/QubEllB3g+Hbf2r8jG0zen4l3G1e8YpFoGnE=; h=MIME-Version:Date:From:To:Cc:Message-Id:In-Reply-To:References: Subject:Content-Type; b=FHiVihnXMJCtM5w1paSlS0oz13IPKDKRyAkduGSWx9Pf/VPeJUWYKPfnOlAGPlenIWhPOQ2mi9V5Vp+p47o6+jj/bYtqDnCXRLtUJu9KoVP0kWcPkm2gOErJtjp+Q8XlOQKDy3AwbwIcvSoN4N/8E1accwShI0NbdiXsJLw7LA0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=X4EBiGbs; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="X4EBiGbs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A39AC116C6; Mon, 1 Dec 2025 15:11:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764601884; bh=CQjhTj/QubEllB3g+Hbf2r8jG0zen4l3G1e8YpFoGnE=; h=Date:From:To:Cc:In-Reply-To:References:Subject:From; b=X4EBiGbs8z0Rj86ZhAnB2c4p2M+Vk7xCd9Ed9kvIW2acaZdd2J7mJhH+TnqcLwx45 tD5ZEF6tIC8YNWPsPilEx8la4vpzaltgybu+/QAn01S+ZKyN58IWLFjCXLIYDtCU+r AXADeMpYX8dfzyFojnNtWYpuWRhUqCdAMxfSBqrq0jbNxB7/GX7C6msMY3PIGwoUJq 46Yuk9y0Eq2XcSx9BzMRS9WQ1PMdgJs6hzSGfXXyRWxVd8c7IO537DZ79+qtEHiUjh ynGNapdjHxWQBMRUWKW+6UPztQcF/cezSldia07YNZdFU54MCQpMYezpLm/vQUXW8x yC+2TE6cl2X+A== Received: from phl-compute-10.internal (phl-compute-10.internal [10.202.2.50]) by mailfauth.phl.internal (Postfix) with ESMTP id 73C3AF4006E; Mon, 1 Dec 2025 10:11:23 -0500 (EST) Received: from phl-imap-15 ([10.202.2.104]) by phl-compute-10.internal (MEProxy); Mon, 01 Dec 2025 10:11:23 -0500 X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtdeggddvheektdefucetufdoteggodetrf dotffvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceu rghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujf gurhepofggfffhvfevkfgjfhfutgfgsehtqhertdertdejnecuhfhrohhmpedfvehhuhgt khcunfgvvhgvrhdfuceotggvlheskhgvrhhnvghlrdhorhhgqeenucggtffrrghtthgvrh hnpefhgeejgfegvdfgkeeugfejheefkeeghfdtleegheejheekgfekjeeluddvveekuden ucffohhmrghinheplhhinhhugidqnhhfshdrohhrghenucevlhhushhtvghrufhiiigvpe dtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegthhhutghklhgvvhgvrhdomhgvshhmthhp rghuthhhphgvrhhsohhnrghlihhthidqudeifeegleelleehledqfedvleekgeegvdefqd gtvghlpeepkhgvrhhnvghlrdhorhhgsehfrghsthhmrghilhdrtghomhdpnhgspghrtghp thhtohepfedpmhhouggvpehsmhhtphhouhhtpdhrtghpthhtoheprhhitghkrdhmrggtkh hlvghmsehgmhgrihhlrdgtohhmpdhrtghpthhtohepshgvsggrshhtihgrnhdrnhdrfhgv lhgusehgmhgrihhlrdgtohhmpdhrtghpthhtoheplhhinhhugidqnhhfshesvhhgvghrrd hkvghrnhgvlhdrohhrgh X-ME-Proxy: Feedback-ID: ifa6e4810:Fastmail Received: by mailuser.phl.internal (Postfix, from userid 501) id 34956780054; Mon, 1 Dec 2025 10:11:23 -0500 (EST) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ThreadId: A9oaoCPaRE3R Date: Mon, 01 Dec 2025 10:11:00 -0500 From: "Chuck Lever" To: "Rick Macklem" Cc: "Sebastian Feld" , linux-nfs Message-Id: In-Reply-To: References: <5e1b3d07-fd80-47d0-bbf8-726d1f01ba54@app.fastmail.com> Subject: Re: LAYOUT4_NFSV4_1_FILES supported? Re: Can the PNFS blocklayout of the Linux nfsd server be used in a production environment? Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Fri, Nov 28, 2025, at 6:16 PM, Rick Macklem wrote: > On Fri, Nov 28, 2025 at 8:24=E2=80=AFAM Chuck Lever w= rote: >> >> >> >> On Fri, Nov 28, 2025, at 3:57 AM, Sebastian Feld wrote: >> > On Thu, Nov 27, 2025 at 5:41=E2=80=AFPM Chuck Lever wrote: >> >> >> >> On Wed, Nov 26, 2025, at 9:14 PM, Zhou Jifeng wrote: >> >> > Hello everyone, I learned through ChatGPT that the PNFS blocklay= out of Linux >> >> > nfsd cannot be used for production environment deployment. Howev= er, I saw >> >> > a technical sharing conference video on YouTube titled "SNIA SDC= 2024 - The >> >> > Linux NFS Server in 2024" where it was mentioned that the PNFS b= locklayout >> >> > of nfsd has been fully maintained, which is contrary to the resu= lt given by >> >> > ChatGPT. >> >> > >> >> > My question is: Can the PNFS blocklayout of nfsd be used for >> >> > production environment deployment? If yes, from which kernel ver= sion can it >> >> > be used in the production environment? >> >> >> >> Responding as the presenter of the SNIA SDC talk: >> >> >> >> There's a difference between "maintained" and "can be deployed in a >> >> production environment". "Maintained" means there are developers >> >> who are active and can help with bugs and new features. "Production >> >> ready" means you can trust it with significant workloads. >> >> >> >> The pNFS block layout type has several subtypes. Pure block, iSCSI, >> >> SCSI, and NVMe. >> > >> > What about the LAYOUT4_NFSV4_1_FILES layout type? Is that still sup= ported? >> >> Above, we're talking about the Linux NFS server... IIRC NFSD never >> supported the NFSv4.1 file layout type. It has a simple experimental >> implementation of the flexfile layout type (the MDS and DS are the >> same server). > Once upon a time Benny Halevy had a single server (in the Linux > kernel) that did file layout. (I remember because that is what I used > for testing the FreeBSD client side.) It even knew how to do striping. > > However, it was a "single server" (MDS and DS in the same Linux kernel= nfsd), > so it was only useful for testing purposes. > > I have no idea if it is still around somewhere, but unless someone wan= ts > to do a lot of work on it, it is definitely not useful for production = sites. I am going to guess that was Dan Muntz's prototype. AFAIK that was never merged upstream, but remains available in archive form at git.linux-nfs.org. NFSD continues to implement only the block-related layout types, plus flexfile (in toy form). --=20 Chuck Lever