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 9B13B2E3EB; Thu, 7 Nov 2024 14:51:29 +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=1730991089; cv=none; b=DQDq9Oc63cjv+Ii1QC05fpUZUkz8UzAQo7tdJXEMvO4HPF/11lVkGA02BC5uwLMrEfejVm5yG4enIeq9eB4xXslaI8FZafMlBFb8awWaZ9vA6c7KMAMwy6FYGFxeDMsvarKfk+ECeaXOB2NhLET6CXUMC6C6OkEq1ZDYtHqpudQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730991089; c=relaxed/simple; bh=UDbLjDFZkSXWs8RR2rQ1qcG0qwDdYETzsAFRQPzaaxI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HdzUYKRSH1XXgR6jTvNuKgxEwfqU+VPAv7IbUNr5qlFOmRX/fIdUScwHIkAASG9BDrvVZjcELJesUaLUDsBb2GnEV5BvVM/EEPoyns3N+ILj6EYSTSx2q2uXMlgRIsVkmWSZY6yugrIBKXPQN/BkxS00JjnXr4TORS7WWhKoInQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=P0ONpL7H; 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="P0ONpL7H" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3496FC4CECC; Thu, 7 Nov 2024 14:51:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730991089; bh=UDbLjDFZkSXWs8RR2rQ1qcG0qwDdYETzsAFRQPzaaxI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=P0ONpL7HT6MEULaIh/I4FgYG7ge9soJcQdKCiqEX9r/Rg9EIi5htmXMPhQ2oL9JJ5 TFFj6fjVpa+sdyhz/XBxpc9UARMq6CIIDlrDMMqKZ/vqNzPkgtlTt/mMRZhpJeZtt0 PaGmi+s9kekxVSXYOqJqy+rB1YY9s5Y8w53ThK/iuGeDsU/BVU8sKhNmWxLW9qjK6C eELFgrvCl4hcmv58tDh4DSOlzo/B4wHUk4jfEL81upYJcNM3RZExIj+5WWfL9+MHAx qIpYityeMmGdWaGn3kpz9DIAj9a4a4HsukXtwVLaeE6Cb1loCfW7XPwc4PLIdhH7vw mZbLCfgP7nIkA== Date: Thu, 7 Nov 2024 14:51:24 +0000 From: Simon Horman To: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= Cc: Qingfang Deng , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ppp@vger.kernel.org Subject: Re: [RFC PATCH net-next] net: ppp: convert to IFF_NO_QUEUE Message-ID: <20241107145124.GW4507@kernel.org> References: <20241029103656.2151-1-dqfext@gmail.com> <20241104115004.GC2118587@kernel.org> <87pln99a28.fsf@toke.dk> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87pln99a28.fsf@toke.dk> On Tue, Nov 05, 2024 at 12:47:27PM +0100, Toke Høiland-Jørgensen wrote: > Simon Horman writes: > > > + Toke > > > > On Tue, Oct 29, 2024 at 06:36:56PM +0800, Qingfang Deng wrote: > >> When testing the parallel TX performance of a single PPPoE interface > >> over a 2.5GbE link with multiple hardware queues, the throughput could > >> not exceed 1.9Gbps, even with low CPU usage. > >> > >> This issue arises because the PPP interface is registered with a single > >> queue and a tx_queue_len of 3. This default behavior dates back to Linux > >> 2.3.13, which was suitable for slower serial ports. However, in modern > >> devices with multiple processors and hardware queues, this configuration > >> can lead to congestion. > >> > >> For PPPoE/PPTP, the lower interface should handle qdisc, so we need to > >> set IFF_NO_QUEUE. For PPP over a serial port, we don't benefit from a > >> qdisc with such a short TX queue, so handling TX queueing in the driver > >> and setting IFF_NO_QUEUE is more effective. > >> > >> With this change, PPPoE interfaces can now fully saturate a 2.5GbE link. > >> > >> Signed-off-by: Qingfang Deng > > > > Hi Toke, > > > > I'm wondering if you could offer an opinion on this. > > Hi Simon > > Thanks for bringing this to my attention; I'll reply to the parent > directly :) Likewise, thanks for following-up on this.