From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ms.lwn.net (ms.lwn.net [45.79.88.28]) (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 7BEF118622; Mon, 4 Nov 2024 18:43:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.79.88.28 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730745803; cv=none; b=X1IyZBr7/ePZm5iqwI2Q5/QjFHavu/8hIKlD1UgBpEtEWNOT1iTNCPxnjQJrr+sWKYGF2qaHxbcjjSGY3qGnEz1sWYsTY2rTWuc7AzB50lbGM5k3TRvG+4KKb6u5sNa1gphwbjyzJ5B3n7NHOgGTVWU2R0TQlfuq0cNDo81CxZM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730745803; c=relaxed/simple; bh=2VDcNMBQ57ajKJb2uc2U477Y7mR5hyVDtXcXisUumWM=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=LA3m367bVwZgG5eSkOkufco/pD+gZnpsUlW646/IgKPVQX6wpwgzonG+CGXKwQO9ZPaaZt5UHukLzFR0MuTwCbpBB98zLQL7jnzOCHW+0XOhzxnd2LZaNpTB9d980/+hE46Nk0pK0MMUkJ03PIV0CBlO/oBrz0QpNUmOE7oZykk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lwn.net; spf=pass smtp.mailfrom=lwn.net; dkim=pass (2048-bit key) header.d=lwn.net header.i=@lwn.net header.b=UvRpqSEj; arc=none smtp.client-ip=45.79.88.28 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lwn.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lwn.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lwn.net header.i=@lwn.net header.b="UvRpqSEj" DKIM-Filter: OpenDKIM Filter v2.11.0 ms.lwn.net 64C2342C30 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lwn.net; s=20201203; t=1730745798; bh=ZBiSE17hrrwJpX5hNgDD0DP9xkL/hgtYPMBna+dA2Ss=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=UvRpqSEjjdfnKG//5rbTuqujf9l+/8qxR4QdGaat/K62RXeQabGof1/dLOmblC8dS ZTgLC59m3yRcshuB6On68ttjbu62a/dL3XFTGo5JFUiE8eLN/Qh+w4JupZtmUdcyh8 HjmqFKhxzEYOusN27iOsbEa0i41w+AsAO0lywYvyTReRAqIhCZr2foMfwK4yCx1+0y k3ehCH4nFNhCE1jqadV9ubvQuf1JAvwxb23by1r+RMkUHhkFodmjg/g1PP08bv3hmY IXac9XIXJ0x9h4bcWaRTEn9hu9yXPTBHQh6/MxxgziuRc2CsCHAUPNlZ68HgTFq7OD 4UNkD60KcTV6A== Received: from localhost (unknown [IPv6:2601:280:5e00:625::1fe]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ms.lwn.net (Postfix) with ESMTPSA id 64C2342C30; Mon, 4 Nov 2024 18:43:18 +0000 (UTC) From: Jonathan Corbet To: Joe Damato , Bagas Sanjaya Cc: netdev@vger.kernel.org, hdanton@sina.com, pabeni@redhat.com, namangulati@google.com, edumazet@google.com, amritha.nambiar@intel.com, sridhar.samudrala@intel.com, sdf@fomichev.me, peter@typeblog.net, m2shafiei@uwaterloo.ca, bjorn@rivosinc.com, hch@infradead.org, willy@infradead.org, willemdebruijn.kernel@gmail.com, skhawaja@google.com, kuba@kernel.org, Martin Karsten , "David S. Miller" , Simon Horman , Linux Documentation , Linux Kernel Mailing List , Linux BPF Subject: Re: [PATCH net-next v5 7/7] docs: networking: Describe irq suspension In-Reply-To: References: <20241103052421.518856-1-jdamato@fastly.com> <20241103052421.518856-8-jdamato@fastly.com> Date: Mon, 04 Nov 2024 11:43:17 -0700 Message-ID: <87v7x296wq.fsf@trenco.lwn.net> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Joe Damato writes: > On Mon, Nov 04, 2024 at 05:52:52PM +0700, Bagas Sanjaya wrote: >> On Sun, Nov 03, 2024 at 05:24:09AM +0000, Joe Damato wrote: >> > +It is important to note that choosing a large value for ``gro_flush_timeout`` >> > +will defer IRQs to allow for better batch processing, but will induce latency >> > +when the system is not fully loaded. Choosing a small value for >> > +``gro_flush_timeout`` can cause interference of the user application which is >> > +attempting to busy poll by device IRQs and softirq processing. This value >> > +should be chosen carefully with these tradeoffs in mind. epoll-based busy >> > +polling applications may be able to mitigate how much user processing happens >> > +by choosing an appropriate value for ``maxevents``. >> > + >> > +Users may want to consider an alternate approach, IRQ suspension, to help deal >> to help dealing >> > +with these tradeoffs. >> > + > > Thanks for the careful review. I read this sentence a few times and > perhaps my English grammar isn't great, but I think it should be > one of: > > Users may want to consider an alternate approach, IRQ suspension, to > help deal with these tradeoffs. (the original) The original is just fine here. Bagas, *please* do not bother our contributors with this kind of stuff, it does not help. jon