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 A48C727A476; Fri, 1 May 2026 12:21:20 +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=1777638082; cv=none; b=lgjxg1GHEUBqsrq2jhUxRq2fcFe5r7flAQyXOJnskuaNEOWZhGKpTuAdrULVECzGKLgh86hpzuxae+VKoFnorKw6+aFADstgoQx5xOFBE2Xk4cuwyrk3mCXdDOlyDjxE825ULV4YLGQTSQLYXzY8MuYGUCJpw+pE+Y3eoyPwD40= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777638082; c=relaxed/simple; bh=TNzDR1TZBAM85v+1er1cq8xj4+1oEevMKUhGnxk3ru8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=J7zW0/cbuC0YA5El/DfmOXlFZBQbrNP9q/HPacngkSY6+GCGHenlrtIk46TJsVIl6uZSHtCWNQDafiSlpIbsK6QDTtz6UJIPv54mW94OISqux0/wxkl4QYets1m8iQCTkr1WSlElOUHausDFhlw7KQm1AL/XFU/lGNtxQYDkd4M= 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=VBNUx1lF; 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="VBNUx1lF" 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=MsrW9P+18F84Qy89FNTzjz238B+2WoEoX3uJ89Kl6oU=; b=VBNUx1lFE3UuUK5wfhNEymEvQL 3FgOUfwExbmAdD/bnOXkAoh+L2C0xOeXB0hsEeI37FXr5G/52UzprljFbbSSH2/EDlZ5JOEsfmskS /D38J4PwGEh/q2JIQZtf54zjTkU4N8m1NXLRggizZEh07YNnLZEsQvM6/ZwCMMzGSGiU=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1wImrk-000oXt-RZ; Fri, 01 May 2026 14:21:08 +0200 Date: Fri, 1 May 2026 14:21:08 +0200 From: Andrew Lunn To: Birger Koblitz Cc: Michal Pecio , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Chih Kai Hsu Subject: Re: [PATCH net-next 3/4] r8152: Add irq mitigation for RTL8157/9 Message-ID: <0fd2b263-bbe0-483d-b2e7-92d76d895b11@lunn.ch> References: <20260428-rtl8159_net_next-v1-0-52d03927b46f@birger-koblitz.de> <20260428-rtl8159_net_next-v1-3-52d03927b46f@birger-koblitz.de> <06a42ba1-b714-45b1-be30-4a793752e495@lunn.ch> <9feb0bc1-b817-46f8-9092-e2beff30ec9d@birger-koblitz.de> <20260429200214.3e8dee67.michal.pecio@gmail.com> <4446ad8c-0f5f-4f5a-8166-557ce9cc91b7@birger-koblitz.de> <62fb1f24-b0cb-4310-a155-1f5cce14d83a@birger-koblitz.de> 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-Disposition: inline In-Reply-To: <62fb1f24-b0cb-4310-a155-1f5cce14d83a@birger-koblitz.de> > However, there is a big difference in CPU-load when running iperf3, > especially with multiple threads: > > WITH the CODE saying it disables IRQ mitigation: > $ iperf3 -c 192.168.3.1 > [ 5] 0.00-10.00 sec 10.3 GBytes 8.83 Gbits/sec > CPU: iperf3 22.5% ksoftirqd 16.6% > > $ iperf3 -c 192.168.3.1 -P4 > [SUM] 0.00-10.00 sec 9.36 GBytes 8.04 Gbits/sec > perf3: 19.3% ksoftirqd 96.7% > > > WITHOUT the CODE saying it disabled IRQ mitigation: > [ 5] 0.00-10.00 sec 10.3 GBytes 8.87 Gbits/sec > CPU: perf3 19.7% ksoftirqd 12.5% > > $ iperf3 -c 192.168.3.1 -P4 > [SUM] 0.00-10.00 sec 10.3 GBytes 8.81 Gbits/sec > CPU: iperf3 22.0% ksoftirqd 46.5% Thanks for doing this performance testing. > My undestanding from the first email by Michal is that the behavior with the > ESHUTOWN is actually harmless and has been seen in the driver already for > the RTL8153. > > So, my suggestion is I drop this part of the patch-series and remove the > IRQ-mitigation code that says it disables the IRQ mitigation as performance > is higher without that code. Agreed. Andrew