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 2B64D17BC1 for ; Thu, 22 Feb 2024 23:07:18 +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=1708643239; cv=none; b=gUKYG/zGSLbqaH9kvUn8NvWUAG9fF4MvdlMlXz0agFm6nqvL4f29BsskOEoErER9/3kE1wPMTZvEhq1HcDb0KJhcDVG8VGYSxFAMPfTZJs9RFKKg1tsltkc/kr/QPMT9qUVU02qKFnKsUJJnq7jLfWq6QUZTWxC7t/KsWRJHsJk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708643239; c=relaxed/simple; bh=tLpCJuni9rb3m7ZM7NstXMA+xk57bKi7V6ML0f7H35A=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=r9htsEkeVY2PY420ZywrD3FUsoxZtBKFbzcRvXvQvEagP9+K/Hd2VIXQffRPkpx/jwWxFaRbR4m5Pak0r7aAXaFsSuLk22FvdN8XRnW2AuXZ1H2gLmJ99k5kHJzBOPYfwEhuOWH1bp7+ENrowLnG6nvtNUob0wOLPNghcfVtfpU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C7zPGvmI; 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="C7zPGvmI" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C60DC433F1; Thu, 22 Feb 2024 23:07:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1708643238; bh=tLpCJuni9rb3m7ZM7NstXMA+xk57bKi7V6ML0f7H35A=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=C7zPGvmIoOM00Pa+BaUg6Gb8zXykl8lKxj3yDTdfqz0XhLG75S7bvoUyR9JWzuX2o vZ04BUm9QphfO1ZI08Oh/CnYT3iGgvoLGoZBiT6CeZvVTX5f9he/Xn7hwNe46LhdIX Gw9ciuOYUPWC/mnydsxniAbEa9CGsut5rSWdyRitPTYzaJRoyZiIhjmZKm4Wy6EYgk +KaSghyQukozxRHekA4UZjn2xIv/ZBDVv2nvfzfCENswabQB6jeTELq1pelo5tna4j 7bSUmfiHhvNe3HFiFMOwEq801XLiU6mnKJHdTFS2MCqaGe1M37LR8NdSZlaDwZXQk1 jK9qRr4aTppfA== Date: Thu, 22 Feb 2024 15:07:17 -0800 From: Jakub Kicinski To: Jiri Pirko Cc: Mateusz Polchlopek , , , , , Lukasz Czapnik Subject: Re: [Intel-wired-lan] [PATCH iwl-next v4 4/5] ice: Add tx_scheduling_layers devlink param Message-ID: <20240222150717.627209a9@kernel.org> In-Reply-To: References: <20240219100555.7220-1-mateusz.polchlopek@intel.com> <20240219100555.7220-5-mateusz.polchlopek@intel.com> <20240221153805.20fbaf47@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 22 Feb 2024 14:25:21 +0100 Mateusz Polchlopek wrote: > >> This is kind of proprietary param similar to number of which were shot > >> down for mlx5 in past. Jakub? > > > > I remain somewhat confused about what this does. > > Specifically IIUC the problem is that the radix of each node is > > limited, so we need to start creating multi-layer hierarchies > > if we want a higher radix. Or in the "5-layer mode" the radix > > is automatically higher? > > Basically, switching from 9 to 5 layers topology allows us to have 512 > leaves instead of 8 leaves which improves performance. I will add this > information to the commit message and Documentation too, when we get an > ACK for devlink parameter. Sounds fine. Please update the doc to focus on the radix, rather than the layers. Layers are not so important to the user. And maybe give an example of things which won't be possible with 5-layer config. Jiri, I'm not aware of any other devices with this sort of trade off. We shouldn't add the param if either: - this can be changed dynamically as user instantiates rate limiters; - we know other devices have similar needs. If neither of those is true, param seems fine to me..