From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D8ABC4363D for ; Fri, 25 Sep 2020 10:57:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A68E3221E5 for ; Fri, 25 Sep 2020 10:57:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601031436; bh=7b1lo3BUiiQw0PSLZhJ2CISK6gXAvCQzhFUyeJ0sssQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=DNZQo3xMn/tCoqAhrwa8EA9nE/RrWxwBSTnK7RZ60pqgQzsjcggkMXGa6tOWA8Rz3 3CMOLl1p8fo7I6qeF8yRm90Cs6HyrtXDIUvoUOMNQBiQDTtOOdkpc8Bb/pnjjqd8zX 0S2gnzVyyLHEVGyJiuv1IZbjvnIFYQOV+Z2WSfV8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727749AbgIYK5P (ORCPT ); Fri, 25 Sep 2020 06:57:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:59458 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726255AbgIYK5P (ORCPT ); Fri, 25 Sep 2020 06:57:15 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BD45E21D91; Fri, 25 Sep 2020 10:57:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601031435; bh=7b1lo3BUiiQw0PSLZhJ2CISK6gXAvCQzhFUyeJ0sssQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WD3u8k12q2ovIgPXUruIhJi0xXpoSHh0X4RkXVhFNjmH/h+iVf74uKkJCG3JETCto 3rImDm6a3qo8KkZMJSqGVbyqghhrfQman+qJd0541C1brPGzgF2kSi8fDf2vdowoYT Zz0ap5y6vs6XipCacJBtlI2vM6X5/D/CGjrQi0+4= Date: Fri, 25 Sep 2020 12:57:29 +0200 From: Greg KH To: Priyaranjan Jha Cc: David Miller , netdev@vger.kernel.org, Priyaranjan Jha Subject: Re: [PATCH linux-4.19.y 0/2] tcp_bbr: Improving TCP BBR performance for WiFi and cellular networks Message-ID: <20200925105729.GA2573626@kroah.com> References: <20200922192735.3976618-1-priyarjha.kernel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200922192735.3976618-1-priyarjha.kernel@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Tue, Sep 22, 2020 at 12:27:33PM -0700, Priyaranjan Jha wrote: > From: Priyaranjan Jha > > Ack aggregation is quite prevalent with wifi, cellular and cable modem > link tchnologies, ACK decimation in middleboxes, and common offloading > techniques such as TSO and GRO, at end hosts. Previously, BBR was often > cwnd-limited in the presence of severe ACK aggregation, which resulted in > low throughput due to insufficient data in flight. > > To achieve good throughput for wifi and other paths with aggregation, this > patch series implements an ACK aggregation estimator for BBR, which > estimates the maximum recent degree of ACK aggregation and adapts cwnd > based on it. The algorithm is further described by the following > presentation: > https://datatracker.ietf.org/meeting/101/materials/slides-101-iccrg-an-update-on-bbr-work-at-google-00 > > (1) A preparatory patch, which refactors bbr_target_cwnd for generic > inflight provisioning. > > (2) Implements BBR ack aggregation estimator and adapts cwnd based > on measured degree of ACK aggregation. Both now queued up, thanks. greg k-h