From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io1-xd32.google.com (mail-io1-xd32.google.com [IPv6:2607:f8b0:4864:20::d32]) (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 5F60C3B29D for ; Thu, 30 Apr 2020 11:58:24 -0400 (EDT) Received: by mail-io1-xd32.google.com with SMTP id 19so1989132ioz.10 for ; Thu, 30 Apr 2020 08:58:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Fqhk2Vn/nvbSMhKuzTCoXyJ8Sc5PQHiWPQUKfSZKFeY=; b=Ee5v0GZ4VkIAJVK/+Xjf4LJff3JM+6czxgE3GPnLdnhtDLjBYHtZiaV+kF1jWp7V4E ihjXg9IguLXAsUA+/JAkrvvwaG/qTM5b+ZkAszlgqzS0cWZBnvqmskny3j9EBgUs0Z61 B+UcZTp7B+SbIVTq2miFytikpE4Ng+sO0yBpAZNtI3z+5BjTzZBf9oPFl8hI71Y/Ga2Z hjVkqTQrOrBgSqnKXErwv0slkJSxOVD5YiOBkRgSsjSjq1SRqVK6XjCSOFepK4cwl/xI 7v2IDThcqBbdKW/q8Q48/S88l+9IH7DeoB7vPRD6DQhMHCXbtPlBCkp6dYnisiwGPco+ eG8w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Fqhk2Vn/nvbSMhKuzTCoXyJ8Sc5PQHiWPQUKfSZKFeY=; b=dCAhVWCMaFIjYP/Hz05N5ZNIbWGSVrReuHA2LHNm41JXpNt/XMwZQOOGM2AW44ZbFq uEp7cXyZdE/Djr54baLyVSbaPH4hUgGZ25I7+WKQa8W2QeMTacNBMaqLDuXBD2pG5g3G 1qBJQsZxRI+sdHAk5ZT4tYKZ5/xMNGOxu1zkC/OVZcHWegVcVxmsyks9AHmkwHwHcGFX cm6Wq9HbStTlRh5JGkZUGtBF5zJ5Hrxj8UZVPHjTLCqNfy6DwsL7udyVXMDV0ezNljSq pfaxkbAn3mJuUDguKFaXPo2CYYw2X/QudU1u0JMhPLrD0BLcY/IlZOldVxLpPgKtfkLy czvw== X-Gm-Message-State: AGi0PuarfBStsN1B1dd3hGA5rUF7mftnqw/iG/fL+Bg1czN6E+N/TmGr zr6hQ+HY0lSozHEzNiBGq0JDbYNX8G17WY0RMhk= X-Google-Smtp-Source: APiQypLsJX16mVdOMESyO73bkaFeeiKx4d3HRppsAuBA4fk6xXGmITEC0GAs7fvf5VrJQaelThMy9qn8DJRgU2ow9I4= X-Received: by 2002:a6b:2b94:: with SMTP id r142mr2577177ior.27.1588262303336; Thu, 30 Apr 2020 08:58:23 -0700 (PDT) MIME-Version: 1.0 References: <5be92b82-ae44-e8f5-9a7a-64fea0093a23@smallnetbuilder.com> In-Reply-To: <5be92b82-ae44-e8f5-9a7a-64fea0093a23@smallnetbuilder.com> From: Dave Taht Date: Thu, 30 Apr 2020 08:58:11 -0700 Message-ID: To: Tim Higgins Cc: Make-Wifi-fast Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [Make-wifi-fast] Uplink vs downlink latency X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 30 Apr 2020 15:58:24 -0000 It would be kind of cool if you added a ubnt uap-pro mesh router to your mix. And (eventually) - reflashed it with our latest openwrt stuff. that's a 3x3 802.11ac product that I know for sure has most of our stuff in the default firmware nowadays. On Thu, Apr 30, 2020 at 7:18 AM Tim Higgins wrote= : > > I take your point, Bob, and agree single-ended latency measurements like = you produce with iperf would be more technically correct. > > I write and review for a consumer audience, where ping is the standard fo= r latency aka lag measurement. So that's why I'm using ping. > That, and the fact that iperf isn't integrated into octoScope's toolset y= et. But they're working on it and all their STA instruments are properly ti= me-synced, so the measurements will be accurate. > > Thank your for all your work in iperf, BTW. The features you've added are= a welcome improvement. > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > Tim > On 4/29/2020 8:32 PM, Bob McMahon wrote: > > I'm thinking ping may not be ideal for benchmarking OFDMA effects on late= ncy. Also, the end/end latency preferred seems to me the socket write() to= final socket read() per that write(). Also, for TCP, there are the connect= times. I realize network stack guys focus on stack related measurements, e= .g. RTT, but the latencies users experience include the application level a= nd system level os interactions. > > Just some food or thought. > > Bob > > > On Wed, Apr 29, 2020 at 5:07 PM Dave Taht wrote: >> >> throughput and latency are interrelated, whats the throughput? >> >> On Wed, Apr 29, 2020 at 2:40 PM Tim Higgins wr= ote: >> > >> > Hi all, >> > >> > I finally have my testbed working the way I want and am starting to ru= n tests to see if OFDMA does anything useful. >> > >> > This will all be covered in detail in an upcoming SmallNetBuilder arti= cle. But I wanted to sanity check something with this esteemed group. >> > >> > The tests are basically the flent rtt_fair_var up and down tests porte= d to the octoScope platform I use for WiFi testing. >> > The initial work was done on flent, with a lot of hand-holding from To= ke. (Thank you, Toke!) >> > >> > Using 4 Intel AX200 STAs on Win10. iperf3 is running traffic using TCP= /IP with unthrottled bandwidth. I've taken Bj=C3=B8rn's idea and have each = STA using a different DSCP priority level, but with TCP/IP traffic, not UDP= . I'm sticking to using CS0-7 equivalents and confirmed that the iperf3 --d= scp values properly translate to the intended WiFi priority levels. Each S= TA has a different priority, either CS0,3,5 or 6 (best effort, excellent ef= fort, video and voice). >> > >> > Ping is used to measure latency and always runs from AP to STA. Only T= CP/IP traffic direction is reversed between the down and uplink tests. >> > >> > One thing that jumps out immediately is that uplink latencies are *muc= h* lower than downlink, with either OFDMA on or off. Attached are three exa= mples. The CDFs are average latency of the 4 STAs. >> > >> > The NETGEAR R7800 is a 4x4 AC Qualcomm-based. I'm using this as a base= line product. >> > >> > The NETGEAR RAX15 is 2x2 AX Broadcom-based. You can see what I mean wh= en I say OFDMA doesn't help. >> > >> > Does this much difference between up and downlink latency pass the sni= ff test? >> > >> > =3D=3D=3D >> > Tim >> > _______________________________________________ >> > Make-wifi-fast mailing list >> > Make-wifi-fast@lists.bufferbloat.net >> > https://lists.bufferbloat.net/listinfo/make-wifi-fast >> >> >> >> -- >> Make Music, Not War >> >> Dave T=C3=A4ht >> CTO, TekLibre, LLC >> http://www.teklibre.com >> Tel: 1-831-435-0729 >> _______________________________________________ >> Make-wifi-fast mailing list >> Make-wifi-fast@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/make-wifi-fast > > > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast --=20 Make Music, Not War Dave T=C3=A4ht CTO, TekLibre, LLC http://www.teklibre.com Tel: 1-831-435-0729