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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 6726CC49ED7 for ; Mon, 16 Sep 2019 14:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 441162067D for ; Mon, 16 Sep 2019 14:39:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729422AbfIPOjs (ORCPT ); Mon, 16 Sep 2019 10:39:48 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:47940 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726649AbfIPOjr (ORCPT ); Mon, 16 Sep 2019 10:39:47 -0400 Received: from localhost (80-167-222-154-cable.dk.customer.tdc.net [80.167.222.154]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 5597E153CB38A; Mon, 16 Sep 2019 07:39:45 -0700 (PDT) Date: Mon, 16 Sep 2019 16:39:32 +0200 (CEST) Message-Id: <20190916.163932.682237439904998758.davem@davemloft.net> To: tph@fb.com Cc: netdev@vger.kernel.org, jonathan.lemon@gmail.com, dsj@fb.com, edumazet@google.com, ncardwell@google.com, dave.taht@gmail.com, ycheng@google.com, soheil@google.com Subject: Re: [PATCH v5 1/2] tcp: Add TCP_INFO counter for packets received out-of-order From: David Miller In-Reply-To: <20190913232332.44036-1-tph@fb.com> References: <20190913232332.44036-1-tph@fb.com> X-Mailer: Mew version 6.8 on Emacs 26.2 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 16 Sep 2019 07:39:47 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Thomas Higdon Date: Fri, 13 Sep 2019 23:23:34 +0000 > For receive-heavy cases on the server-side, we want to track the > connection quality for individual client IPs. This counter, similar to > the existing system-wide TCPOFOQueue counter in /proc/net/netstat, > tracks out-of-order packet reception. By providing this counter in > TCP_INFO, it will allow understanding to what degree receive-heavy > sockets are experiencing out-of-order delivery and packet drops > indicating congestion. > > Please note that this is similar to the counter in NetBSD TCP_INFO, and > has the same name. > > Also note that we avoid increasing the size of the tcp_sock struct by > taking advantage of a hole. > > Signed-off-by: Thomas Higdon Applied.