From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-x22b.google.com (mail-wr0-x22b.google.com [IPv6:2a00:1450:400c:c0c::22b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 14CA33B2A3 for ; Thu, 13 Apr 2017 23:12:06 -0400 (EDT) Received: by mail-wr0-x22b.google.com with SMTP id c55so45147230wrc.3 for ; Thu, 13 Apr 2017 20:12:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=uyD3UG8PnlEPbqakAE6gz/IUbIXiOqnVYGyGnr996wA=; b=INp+Om4B+xLDgzTiagEYMUeGs5ivhe6pxjPC6P1YmNgxKuv7tY8LShNReLGYfDyA+s kFIXGeo9JsYget0OkaWuySn1HzTcGtGfzmECHFKbbSdFddDxhzBi4KYGE8ypELzq9ovg LlMyX8one9yRZtnV4Fjr0X2vftPFOadx7aS4BK4J/r2CDI5DRqb917HQy51ZMBKIz9ZE 5VqQFB1wxFwfWpnKyc9NYKjXkiGVGUMPHGNU00Ntpub8W5vV49VwsLFItOk/TQxfHbx6 j9c0ys6nw2XYX0TPjQl6VGNt8G1W2H6mwp9qbJrPl1zJbx+s5OkZeZkQ3iQWCrLeKhiE J1hA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=uyD3UG8PnlEPbqakAE6gz/IUbIXiOqnVYGyGnr996wA=; b=Ci/56ZkQOEh0ni7oMascuNsMiDiMk6zU6MzBJgYi1YPRAb5PW2Juq1YSdZj/m3ingJ UAP2dNCBQNOWFYyUshOJu1Obvqls6wPW5MLKi0D2SPMzkEF0B+YOFDo3oDOYLJozxmwi oekfeTfBqQN/4KnIyxLhuP4HldRrVpdCOzHo4t5A97/uoqAoij0PZOMcEZBlDSlAcY4n mp0K668yQ2H2YZMy7tr8nQyujqHCSCNptHn+NdvH6n9vkrdIxyYGoO7TDCjW75g6Lr50 97VjbvwTPc+Ftl59KTK/Q7VHaxhsWx6HTMCXcBY4oTKpgfUsMcng/DC3lgrMT/vjJc4G F/JQ== X-Gm-Message-State: AN3rC/5pq5v5+QnT1qULk3LwaHwHhBJkStzAZYmMWgfRStoxOXvZimkY xWqPiYPY8EeP2YuBRRZ5hxUXfEdn+cHy X-Received: by 10.223.128.65 with SMTP id 59mr6042833wrk.119.1492139525650; Thu, 13 Apr 2017 20:12:05 -0700 (PDT) MIME-Version: 1.0 Received: by 10.28.49.135 with HTTP; Thu, 13 Apr 2017 20:12:05 -0700 (PDT) From: Aaron Wood Date: Thu, 13 Apr 2017 20:12:05 -0700 Message-ID: To: bloat Content-Type: multipart/alternative; boundary=94eb2c068e9261c0ed054d17ce27 Subject: [Bloat] sch_fq pacing rate: Xbps, but at which layer in the network stack? X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Apr 2017 03:12:07 -0000 --94eb2c068e9261c0ed054d17ce27 Content-Type: text/plain; charset=UTF-8 When I was testing with my iPerf changes, I realized that the sch_fq pacing (which in iperf is set via setsockopt()), is pacing at a bandwidth that's set at a pretty low level in the stack (which makes sense). This is different from the application pacing that iperf does (which is pacing the goodput). But it's not clear to me where the X bps determination is being made. My current guess is that it's at the interface level (since that's where sch_fq is), and so it's approximately "bytes on the wire", minus preambles and inter-packet spacing, and whatnot. And so it's including all the 802.x headers involved (vlan tags, qos tags, source/dest macs, etc). Is this correct? -Aaron --94eb2c068e9261c0ed054d17ce27 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
When I was testing with my iPerf changes, I realized that = the sch_fq pacing (which in iperf is set via setsockopt()), is pacing at a = bandwidth that's set at a pretty low level in the stack (which makes se= nse).=C2=A0 This is different from the application pacing that iperf does (= which is pacing the goodput).

But it's not clear to = me where the X bps determination is being made.=C2=A0 My current guess is t= hat it's at the interface level (since that's where sch_fq is), and= so it's approximately "bytes on the wire", minus preambles a= nd inter-packet spacing, and whatnot.=C2=A0 And so it's including all t= he 802.x headers involved (vlan tags, qos tags, source/dest macs, etc).=C2= =A0 Is this correct?

-Aaron
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