From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) (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 0560D3B2A4 for ; Fri, 22 Jan 2021 02:04:47 -0500 (EST) Received: by mail-ej1-x631.google.com with SMTP id g12so6184908ejf.8 for ; Thu, 21 Jan 2021 23:04:47 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=yA2YzuEjY2lfQSqbFdlf39cv4AzBdIOGqvMOKPKhdao=; b=glP0PkDW7fMcHzLMMCNkT1obRut/E4aRNSFsKW9LnTZa4t6NKEphk3cl9wKBxuqgIB so0M+Kvgcg8NvtrQ3b7pwKUtPcmZTbtEZ47qpkhITMmzaLF1UjMv2YzrOt2St4N5zNps U3K6mJ8L6Vkq+E/Jb5JrKxGkJn73FwineMATE= 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; bh=yA2YzuEjY2lfQSqbFdlf39cv4AzBdIOGqvMOKPKhdao=; b=AfNwyNU56HiCW1HvuWoO9i4pR6DcB5Is4QhV+nLR+W4ZpK+wSKbEF6kIMnR+ZCHqp4 ooXNKtF8lorUiHHo6RHU2lig+KXWj23HpQOWQyi8VLU5KZja1dKYdZCjDvl2yZ7HR9LG Zd/6Sh/reTbNGsX03aOksxd0Ma4PP/BtxZ3w6OFmVqdjgDv8cvfKrvacyU+hKtfT0Iwc Vlkm1uVwPWLXakg+t83DSGE8kU2871pyHEEz/t2F4aW2FcSGkXzabWsGBntc0KuvcX7L BW6OyvUsR+6x3aYE+b9ZGIeDdFSC6ISAkEorwVUDHhQwvliFyG87MkjLXHYRgfpfXCHe FF5Q== X-Gm-Message-State: AOAM531MejSyLP2irO0tQiHJvnuz92AVBhOSwYo6xMG82FIdZUBD/yNW DJyXdtaUtK/G2O6Ob0i++XnFmVMlh2xbv5svk0pmJ8iL3qdLprg0KQDKhkQSS3+OsGPQq2kZTzx eBkkKcxsImzBh3UGQVHkVw893EVlPKZDA7mKA+1j5qSE2GgfxNA== X-Google-Smtp-Source: ABdhPJyqDmYSpMPf9nzPnrFCCvOoY0cd4uj+Ii428yw2pWlZXvXl4LPouCPpnPKiicYNZzVq8Ho5QApuZx/FnJ3CVPs= X-Received: by 2002:a17:906:c410:: with SMTP id u16mr1959836ejz.159.1611299086872; Thu, 21 Jan 2021 23:04:46 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Bob McMahon Date: Thu, 21 Jan 2021 23:04:36 -0800 Message-ID: To: Tim Higgins Cc: Make-Wifi-fast Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="000000000000ba3ef205b977cdb9" Subject: Re: [Make-wifi-fast] Fun with DSCP and 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: Fri, 22 Jan 2021 07:04:48 -0000 --000000000000ba3ef205b977cdb9 Content-Type: multipart/alternative; boundary="000000000000b38b0a05b977cd41" --000000000000b38b0a05b977cd41 Content-Type: text/plain; charset="UTF-8" I can't speak to these chips or drivers but we have the ability to fault isolate latency via much more advanced network telemetry. This type of testing seems likely to be conflating buffer bloat with latency. They're two different phenomena. iperf 2.1.0 has a --near-congestion option to help test latency rather than bloat. It's not perfect but is reproducible for controlled networks. Also, probably a good idea to synchronize clocks. NTP stratum-1 servers can be built with a raspberry pi and a GPS hat. One can yse PTP to distribute. The average crystal ends up being about as accurate as a mechanical watch DIY Raspberry Pi GPS stratum 1 clock Bob On Thu, Jan 21, 2021 at 1:09 PM Tim Higgins via Make-wifi-fast < make-wifi-fast@lists.bufferbloat.net> wrote: > Hi all, > > I've found unexpected behavior running simultaneous ping and TCP/IP tests > using multiple AX200 > based Linux STAs and different iperf3 --dscp values for each STApal. > > Details are in the document linked below. I'd appreciate it if you could > read and comment. > > _ > https://docs.google.com/document/d/1XB-DaqBzDDprdb-SorWK5sSwtzMhrOSYXiDOrGU_fq4/edit?usp=sharing_ > < > https://docs.google.com/document/d/1XB-DaqBzDDprdb-SorWK5sSwtzMhrOSYXiDOrGU_fq4/edit?usp=sharing > > > > Thanks > =========== > Tim Higgins > > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast -- This electronic communication and the information and any files transmitted with it, or attached to it, are confidential and are intended solely for the use of the individual or entity to whom it is addressed and may contain information that is confidential, legally privileged, protected by privacy laws, or otherwise restricted from disclosure to anyone else. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, you are hereby notified that any use, copying, distributing, dissemination, forwarding, printing, or copying of this e-mail is strictly prohibited. If you received this e-mail in error, please return the e-mail to the sender, delete it from your computer, and destroy any printed copy of it. --000000000000b38b0a05b977cd41 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I can't speak to these chips or drivers but we have th= e ability to fault isolate latency via much more advanced network telemetry= .=C2=A0

This type of testing seems likely to be conflating buffer b= loat with latency. They're two different phenomena.

iperf 2.1.0 has a --near-conge= stion option to help test latency rather than bloat. It's not perfect b= ut is reproducible=C2=A0for controlled=C2=A0networks.

Also, probably= =C2=A0a good idea to synchronize clocks.=C2=A0 NTP stratum-1 servers can be= built with a raspberry pi and a GPS hat. One can yse PTP to distribute.
The average crystal ends up b= eing about as accurate as a mechanical watch

On Thu, Jan 21, 2021 at 1:09 PM Tim Higgins v= ia Make-wifi-fast <make-wifi-fast@lists.bufferbloat.net> wrote:
Hi all,

I've found unexpected behavior running simultaneous ping and TCP/IP tes= ts using multiple AX200
based Linux STAs and different iperf3 --dscp values for each STApal.

Details are in the document linked below. I'd appreciate it if you coul= d read and comment.

_= https://docs.google.com/document/d/1XB-DaqBzDDprdb-SorWK5sSwtzMhrOSYXiDOrGU= _fq4/edit?usp=3Dsharing_
<https://docs.google.com/document/d/1XB-DaqBzDDprdb-SorWK5sSwtzMhrOSYXiDOr= GU_fq4/edit?usp=3Dsharing>

Thanks
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Tim Higgins

_______________________________________________
Make-wifi-fast mailing list
M= ake-wifi-fast@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/make-wif= i-fast

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