From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) (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 606B73B29E for ; Tue, 10 Aug 2021 00:52:08 -0400 (EDT) Received: by mail-wr1-x42f.google.com with SMTP id c9so24431636wri.8 for ; Mon, 09 Aug 2021 21:52:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=FpdF93b2CBMJfctDo1KK7gJ5TmgOsHqdDiDLFf95hX0=; b=Hiav4oaVq8Bp23s19wRp6wFYjIRGLS4dVlfca4TVL5hm0BmHXf67r3vmEE+ijlUmJ5 eBKb7OuVgRqcynKZ7WCRhnH+UInWcyN0fGwgb2l2i6ifFnI/OOCj3rHW2pLT2y6VeGvM 8DMmfVw098lG9CfJJ2lpEPbUU684tOIUeA/CcWpt0tskTiL/L/8ufuitduLOMcVbY6uv diJxiEAiQmd5Befhbvf/gV3/Z111yw4/tRy9zuWZvi3REJe3vF32vwm1sjX3py+ip4jC lA3IQmOXsDuUeB1cTfcfSM61JtUOWCLLqqoK5AkcS/DbY1pLOe8OZDV9Le6qdIDV0g3o pnzQ== 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=FpdF93b2CBMJfctDo1KK7gJ5TmgOsHqdDiDLFf95hX0=; b=pemeEb87r0BlRdY9J+n0F4V+kD16SsWlWswhe9w8WGf6IQAW+K+CEV5WExzWPO0iSK BBxvw0JAnibYqg3CLc0f0Co1MuU56SHdiC0dbR3zT1uo36P/Cfynq0V2bduUqy++QbQB tuIMHIGuyjreOGNSHQ55X7YN9qG6alsi8N9C4M9U/MlknfKnaD6Q2feaUlYvNOUE4v1d Te96j0Kyj538fSiKF1echf6gEcPdCL87dQVYbQOY/IhWwQO/s9YgVRh7z/Ot6jz+zVzP 9s9YGMc4BhA/Z6wsNwfwhLjgfs6mloNAEonK8K0/TN8nOS74wUwlV2RYwzkJTyX+mly8 HIKA== X-Gm-Message-State: AOAM5339OWLrvBgU3Aop1yckvdo4SGcigPLlVKzN4lrupbdj7OIqXhRp Ayug43GE2AAoMdqVw8NeC++snah7p8qQiZeNF4RJIw== X-Google-Smtp-Source: ABdhPJybVx6HS0S+XzxvTmLbWf/YO7mY7W7h/X25CWYdzryCCpjTn2NZ147LegKe/rC+sM18lVDJGDgpECnqTgW/JbI= X-Received: by 2002:adf:d087:: with SMTP id y7mr28007188wrh.323.1628571126810; Mon, 09 Aug 2021 21:52:06 -0700 (PDT) MIME-Version: 1.0 References: <45E365CA-A298-44D1-8D4C-2E48CB4DC0B7@apple.com> In-Reply-To: From: Matt Mathis Date: Mon, 9 Aug 2021 21:51:54 -0700 Message-ID: To: dave.collier-brown@indexexchange.com Cc: bloat Content-Type: multipart/alternative; boundary="00000000000082107b05c92d4301" Subject: Re: [Bloat] [Rpm] Airbnb 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: Tue, 10 Aug 2021 04:52:08 -0000 --00000000000082107b05c92d4301 Content-Type: text/plain; charset="UTF-8" I am part of the M-Lab team. For years we published a "jitter" metric that I considered to be bogus, basically max_rtt - min_rtt, (which were builtin Web100 instruments). In 2019, we transitioned from web100 to "standard" linux tcp_info, which does not capture max_rtt. Since the web100 jitter was viewed as bogus, we did not attempt to reconstruct it, although we could have. Designing and implementing a new latency metric was on my todo list from the beginning of that transition, but chronically preempted by more pressing problems. It finally made it to the top of my queue which is why I am suddenly not lurking here and the new rpm list. I was very happy to see the Apple responsiveness metric, and realized that M-Lab can implement a TCP version of it, that can be computed both in real time on future tests and retroactively over archived tests collected over the last 12 years. This quick paper might be of interest: Preliminary Longitudinal Study of Internet Responsiveness . Thanks, --MM-- The best way to predict the future is to create it. - Alan Kay We must not tolerate intolerance; however our response must be carefully measured: too strong would be hypocritical and risks spiraling out of control; too weak risks being mistaken for tacit approval. On Mon, Aug 9, 2021 at 5:27 PM Dave Collier-Brown < dave.collier-brown@indexexchange.com> wrote: > Knowing programmers, I'd more likely assume latency when it's easiest to > measure. At a guess, either > > - average of upload or download > - average of download (as it comes first) > > --dave (call me "Wally" (:-)) c-b > > > On 2021-08-09 4:24 p.m., Jonathan Morton wrote: > > On 9 Aug, 2021, at 10:25 pm, Dave Collier-Brown wrote: > > My run of it reported latency, but without any qualifiers... > > One would reasonable assume that's idle latency, then. > > - Jonathan Morton > _______________________________________________ > Bloat mailing listBloat@lists.bufferbloat.nethttps://lists.bufferbloat.net/listinfo/bloat > > -- > David Collier-Brown, | Always do right. This will gratify > System Programmer and Author | some people and astonish the restdave.collier-brown@indexexchange.com | -- Mark Twain > > > *CONFIDENTIALITY NOTICE AND DISCLAIMER** : This telecommunication, > including any and all attachments, contains confidential information > intended only for the person(s) to whom it is addressed. Any dissemination, > distribution, copying or disclosure is strictly prohibited and is not a > waiver of confidentiality. If you have received this telecommunication in > error, please notify the sender immediately by return electronic mail and > delete the message from your inbox and deleted items folders. This > telecommunication does not constitute an express or implied agreement to > conduct transactions by electronic means, nor does it constitute a contract > offer, a contract amendment or an acceptance of a contract offer. Contract > terms contained in this telecommunication are subject to legal review and > the completion of formal documentation and are not binding until same is > confirmed in writing and has been signed by an authorized signatory.* > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat > --00000000000082107b05c92d4301 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I am part of the M-Lab team.

For years = we published a "jitter" metric that I considered to be bogus, bas= ically max_rtt - min_rtt, (which were builtin Web100 instruments).

In 2019, we transitioned=C2=A0from web100 to "standar= d" linux tcp_info, which does not capture max_rtt.=C2=A0 =C2=A0Since t= he web100 jitter was viewed as bogus, we did not attempt to reconstruct it,= although we could have.=C2=A0 =C2=A0Designing and implementing a new laten= cy=C2=A0metric was on my todo list from the beginning of that transition, b= ut chronically preempted by more pressing problems.

It finally made it to the top of my queue which is why I am suddenly not = lurking here and the new rpm list.=C2=A0 I was very happy to see the Apple = responsiveness metric, and realized that M-Lab can implement a TCP version= =C2=A0of it, that can be computed both in real time on future tests and ret= roactively over archived tests collected over the last 12 years.
=
This=C2=A0quick paper might be of interest:=C2=A0Preliminary Longitudinal Study of Internet Responsiveness
=
.=C2=A0=C2=A0
Thanks,
--MM--
The best way to = predict the future is to create it. =C2=A0- Alan Kay

We must not tol= erate intolerance;
=C2=A0 =C2=A0 =C2=A0 =C2=A0however= our response must be carefully measured:=C2=A0
=C2=A0 =C2=A0 =C2= =A0 =C2=A0 =C2=A0 =C2=A0 too strong would be hypocritical and risks spirali= ng out of control;
=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 too = weak risks being mistaken for tacit approval.
=


On Mon, Aug 9, 2021 at 5:27 PM Dave Collier-Brown <= ;dave.collier-brown= @indexexchange.com> wrote:

Knowing programmers, I'd more likely assume latency when it's ea= siest to measure. At a guess, either

  • average of upload or download
  • average of download (as it comes = first)

--dave (call me "Wally" (:-)) c-b


On 2021-08-09 4:24 p.m., Jonathan Morton wrote:= 

On 9 Aug, 2021, at 10:25 pm, Dave Collier-Brown <dave.collier-brown@=
indexexchange.com> wrote:

My run of it reported latency, but without any qualifiers...

One would reasonable assume that's idle latency, then.

 - Jonathan Morton
_______________________________________________
Bloat mailing list
Bloat@list=
s.bufferbloat.net
=
https://lists.bufferbloat.net/listinfo/bloat

--=20
David Collier-Brown,         | Always do right. This will gratify
System Programmer and Author | some people and astonish the rest
d=
ave.collier-brown@indexexchange.com |              -- Mark Twain

CONFIDENTIALITY NOTICE A= ND DISCLAIMER= =C2=A0: This telecommunication, including any and all attachments, contains= confidential information intended only for the person(s) to whom it is addressed. Any dissemination, distribution, copying or discl= osure is strictly prohibited and is not a waiver of confidentiality. If you= have received this telecommunication in error, please notify the sender im= mediately by return electronic mail and delete the message from your inbox and deleted items folders. This tel= ecommunication does not constitute an express or implied agreement to condu= ct transactions by electronic means, nor does it constitute a contract offe= r, a contract amendment or an acceptance of a contract offer. Contract terms contained in this telecommunication ar= e subject to legal review and the completion of formal documentation and ar= e not binding until same is confirmed in writing and has been signed by an = authorized signatory.

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Bloat mailing list
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