From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) (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 B2BF13207; Fri, 21 Jun 2024 03:12:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.67.10.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718939574; cv=none; b=acb4Bgd21TWdNxye/6wWcRouyQsgH2NGUM9XTpPkDBJjeNNp9bSxNYJKTWp59KNwp7I/LPYQvi8PkB4Lxuw8KIFRSZwPOT68GM+78LpJECmriXwzDd7HmsVAnwfUEljK8Vl6SKJeuWZI6QndhSRw0Rd7waaJddGX2yqlJIqf29I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718939574; c=relaxed/simple; bh=uCSUHcTauHBP6zOn6YHuV7MpFi2lKxVbRouK6xsPz4Q=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DXgmF7VbjD1NgqbVvUhCcKWLYJPGBltw8XDCfTX/sz0lmnSfGGkBAfEaZlbj7BbeaKzBPnrdNSRTFfsFcWNs1qCCKuCZcw+G/M+XmS/UilBI9UJCTnKMNqx9H2ljFgR+wXPpajvBigmslx+/NHgK+SwNaC09uAARCQ2IIByANsM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch; spf=pass smtp.mailfrom=lunn.ch; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b=PbsVJysu; arc=none smtp.client-ip=156.67.10.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lunn.ch Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="PbsVJysu" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=WO33cNTPn9NUUeGGOkVxo3S92qWrXCg9qOPXQk9jSr0=; b=PbsVJysujVOHC+yOLzuwpAi3ei kTz4cujpB9sVSjqxrx9NKMH9EhttayUvRNN0/ZRe7iIFVr+iBK61p3IsPS1G1DsTohPGqWuk3re4a YfJhVyLlnH0ufsUZvlfJmzTfE+cdg1GcHdq2eSmNoTJixDxcDUxXHmYdkH2Bus/2KlKs=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1sKUhP-000cmD-QD; Fri, 21 Jun 2024 05:12:27 +0200 Date: Fri, 21 Jun 2024 05:12:27 +0200 From: Andrew Lunn To: Furong Xu <0x1207@gmail.com> Cc: Serge Semin , "David S. Miller" , Alexandre Torgue , Jose Abreu , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Joao Pinto , Simon Horman , netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, xfr@outlook.com, rock.xu@nio.com Subject: Re: [PATCH net-next v1] net: stmmac: xgmac: increase length limit of descriptor ring Message-ID: <788c2744-e1c0-4338-9b86-9119d31841f1@lunn.ch> References: <20240620085200.583709-1-0x1207@gmail.com> <20240621102627.000060d6@gmail.com> 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: <20240621102627.000060d6@gmail.com> > Heavy incoming traffic on some heavy load system, the max 1024 limit defined > by DMA_MAX_RX_SIZE in drivers/net/ethernet/stmicro/stmmac/common.h is too > few to achieve high throughput for XGMAC. > With this patch, ethtool can set a new length than 1024 Please include some benchmark results to show the improvement. But at some point, more buffers don't help you. If you are consistently overloaded, you will still overflow the buffers. So you might want to look at where is the bottleneck and how do you prioritise processing packets over whatever else is loading the system. Maybe this would help, if the bus is the problem: https://www.spinics.net/lists/netdev/msg1006370.html Andrew