From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BF63B37B413; Tue, 16 Jun 2026 02:17:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781576227; cv=none; b=PVwmllBjv9fIvXWSxqMt8Hi9Thw61Ej3gAmRfZajEutcnXoziHxtWwJrgnrG46JVK3yOAeCVvNGgaBchvxEluW6yjXX2Oe8XfQVWmXw2mistMd9GzjtHxHSbrgqoBclI1c5aPANj3OwmUds8bpV9m0YWe3vzTfM6yXvfFu4eRp0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781576227; c=relaxed/simple; bh=iYuwh/QjPCaFltZgY1oNyGfCkwfgJLRV5G8y/pey57o=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=dDwyFBXPviVRojsR9lz2pUixS+AkXHmOkoMenmN6JcArVvgoIg1fD02gTj/McWu8yE9fav7qzQO1tephnUuFpleif7+ah3gmC2610VsjDOgVhWOfhxrU12SM8YVwJbAY2j4RhLTYxBI/IJuo3lnFGqNF+lva9AobhhaBS4CREbI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OStTHS9c; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OStTHS9c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6E4D1F000E9; Tue, 16 Jun 2026 02:17:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1781576226; bh=xD+Oip3IRpQPzSxenYyTvneudjF43QmGVA6/28MSifo=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=OStTHS9ceHewKrSU9o18QwJHMw4AaB6qp16uTX1ZTaLPmPIBVJ1pSMw1/lJ3jQeA+ G1Vj/m3qrDZP/n3iLx4qkdSkdRQD7RAXYKDxBmdm/4HEpJs6zXA5x6lFVaHtN17NAI hw74FSwUS74Zigh7lKdAGeN2AS+22bqzFTCbWu0athb/SR13nF5ZZT3dcoGyc1vCHL BHjECOGWU8Y7vIwGaDgVr1A4bbBgAtxKo1f8Q6Qn65+vqV6m5HJXYSEBJOYKaMqWjV i75kqeYQMypXa9zyHUjO7tSEBlL7sd/dgKS8PXvUFzFLOPYGDDsrrFm92iX/5Qa371 H7KQ1oHer7+Qw== Date: Mon, 15 Jun 2026 19:17:04 -0700 From: Jakub Kicinski To: edumazet@google.com, ncardwell@google.com Cc: chia-yu.chang@nokia-bell-labs.com, jolsa@kernel.org, yonghong.song@linux.dev, song@kernel.org, linux-kselftest@vger.kernel.org, memxor@gmail.com, shuah@kernel.org, martin.lau@linux.dev, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, horms@kernel.org, dsahern@kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, jhs@mojatatu.com, stephen@networkplumber.org, davem@davemloft.net, andrew+netdev@lunn.ch, donald.hunter@gmail.com, kuniyu@google.com, ij@kernel.org, koen.de_schepper@nokia-bell-labs.com, g.white@cablelabs.com, ingemar.s.johansson@ericsson.com, mirja.kuehlewind@ericsson.com, cheshire@apple.com, rs.ietf@gmx.at, Jason_Livingood@comcast.com, vidhi_goel@apple.com Subject: Re: [PATCH v2 net-next 1/1] tcp: Replace min_tso_segs() with tso_segs() CC callback for TCP Prague Message-ID: <20260615191704.31be22da@kernel.org> In-Reply-To: <20260615185102.5e8de52d@kernel.org> References: <20260614071756.239686-1-chia-yu.chang@nokia-bell-labs.com> <20260615185102.5e8de52d@kernel.org> Precedence: bulk X-Mailing-List: linux-kselftest@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 Mon, 15 Jun 2026 18:51:02 -0700 Jakub Kicinski wrote: > On Sun, 14 Jun 2026 09:17:56 +0200 chia-yu.chang@nokia-bell-labs.com > wrote: > > This patch replaces existing min_tso_segs() with tso_segs() CC callbak > > for CC algorithm to provides explicit tso segment number of each data > > burst and overrides tcp_tso_autosize(). > > > > No functional change. > > Eric, Neal, looks good? > > The min rtt thing in tcp_tso_autosize() helps a bit but if the sender > gets congested for a longer stretch min_rtts on new connections are > high and we're back to sending small TSO, keeping the sender overloaded. > Which is to say - I _hope_ this also solves some of Meta's problems :) Ugh, I didn't see the Sashiko report, it's only CCed to the author and bpf@, not to netdev :/ The zero-check sounds legit. Let's revisit this after the merge window.