From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-il1-x130.google.com (mail-il1-x130.google.com [IPv6:2607:f8b0:4864:20::130]) (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 198353B29E for ; Mon, 17 May 2021 11:49:57 -0400 (EDT) Received: by mail-il1-x130.google.com with SMTP id k4so2788339ili.4 for ; Mon, 17 May 2021 08:49:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nathan.io; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=NrwFxE82/gsDxtu/y4qHq8pu3ye3DxXMsNGerBxKano=; b=pupcWTjohLbHwLcvCWxEw6ST349e0vC1tUjWmxQR0s0M07E7IAdRBb0NHCvZCrTI3e B28OP43jR7NxVNCdzjIRODIKeSQifnI9+YjncfdE4ljBcELxxq7E5728/LtHj3EAORmi 2Z59jZ/HzQ24inmGpcwYsIM40vovz1hdqb7sJ8Tziz9CEvl4uxZjVIShwBokEpa3yAq/ coAhEh+GIIHdRoLZCXphVhIHOy2ep84b+7nHaA2dZu2hxDlMgK4NK/8YKpsJTs8cOFI8 x/pqHdzRDLjec/UrMIguW0Evs0HFNkjehypg0wp7suOvf1PlWouon2eRanQaR1jDCi/C Q7kA== 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=NrwFxE82/gsDxtu/y4qHq8pu3ye3DxXMsNGerBxKano=; b=fZf+6b5JpBXO5gjq5gEFTyHu7IiKLkTOr/USND4lLf9XsgOEMb43J7GuftuL2KYX1C 8gb4EHQ7yjlMjyQML6+uL50McHZLIZLRDkn0FCMbPCaYpHs/TvhprFFm9ocDY2CzQt7X K51Zehsgp73AVcSBFQO0MQfmTqemQB+VAdk5qzRhQSzy6VdsVtxHAdN78B8SwlfG7INt Op2pOPD5p5+TnXmOlEoT/NLY3bZ1qYnerFdIHkzNvSwDVjw7c95vyktdJvR9vhti/h3g 1vfutGjSAwKZzvOVLP4G2qdqETsWnTpIwLgP9XEbZw48pM7YKEWeLlOCB33MWN0wN5v5 /EKQ== X-Gm-Message-State: AOAM5317DFiOIR2XvhA6hxcs5GE3DrpXInnYPysZA1RfBN9kAlwOq86e TnVUVw5Ed5Czy/Inv5cgtPv/JBZofFnKSMZVvBak+g== X-Google-Smtp-Source: ABdhPJyu1utE2pSCIBxHFA8yeEGvSCYbk+HQmSdFhlXzwdY90ySHHhZ/e5RTeTqIAJtzNFM7owyU262+66CMjoyeVKw= X-Received: by 2002:a05:6e02:1b06:: with SMTP id i6mr262242ilv.139.1621266596370; Mon, 17 May 2021 08:49:56 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Nathan Owens Date: Mon, 17 May 2021 08:49:45 -0700 Message-ID: To: Neal Cardwell Cc: Matt Mathis , starlink@lists.bufferbloat.net, bloat Content-Type: multipart/alternative; boundary="00000000000090316d05c2888b85" X-Mailman-Approved-At: Mon, 17 May 2021 12:03:23 -0400 Subject: Re: [Bloat] [Starlink] starlink bloat in review 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: Mon, 17 May 2021 15:49:57 -0000 --00000000000090316d05c2888b85 Content-Type: text/plain; charset="UTF-8" Here's someone's monitoring setup with high frequency pings: https://snapshot.raintank.io/dashboard/snapshot/eL3CqijxCvIn0yJz05QQkg47OTNlk05A?orgId=2 Looks better than the 50-115ms reported. On Mon, May 17, 2021 at 8:34 AM Neal Cardwell wrote: > On Sat, May 15, 2021 at 7:00 PM Matt Mathis via Bloat > wrote: > > > > I don't understand: starlink doesn't terminate the TCP connection, > > does it? Or are you referring to YT's BBR adequately addressing > > Starlinks variable RTT? "Adequately" is probably the operative word. > > It is not too hard to imagine what goes wrong with BBR if the actual > > path length varies, and on an underloaded network, you may not be able > > to even detect the symptoms. > > On that note, the article mentions: > "Starlink itself measures ping times for Counter-Strike: Go and > Fortnite in its app, and I rarely saw those numbers dip below 50ms, > mostly hovering around 85-115ms." > > If the range 50ms to 115ms is representative of two-way propagation > delays on their network, then it sounds like BBR can probably perform > reasonably well in that environment. The algorithm is designed to > tolerate factor-of-two variations in RTT and still maintain full > utilization, if there is reasonable buffering. > > neal > _______________________________________________ > Starlink mailing list > Starlink@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/starlink > --00000000000090316d05c2888b85 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Here's someone's monitoring setup with high f= requency pings: https://snapshot.raintank.io/da= shboard/snapshot/eL3CqijxCvIn0yJz05QQkg47OTNlk05A?orgId=3D2
L= ooks better than the 50-115ms reported.

On Mon, May 17, 2021 at 8= :34 AM Neal Cardwell <ncardwell@= google.com> wrote:
On Sat, May 15, 2021 at 7:00 PM Matt Mathis via Bloat
<bloat@= lists.bufferbloat.net> wrote:
>
> I don't understand: starlink doesn't terminate the TCP connect= ion,
> does it?=C2=A0 =C2=A0Or are you referring to YT's BBR adequately a= ddressing
> Starlinks variable RTT?=C2=A0 =C2=A0"Adequately" is probably= the operative word.
> It is not too hard to imagine what goes wrong with BBR if the actual > path length varies, and on an underloaded network, you may not be able=
> to even detect the symptoms.

On that note, the article mentions:
=C2=A0 "Starlink itself measures ping times for Counter-Strike: Go and=
Fortnite in its app, and I rarely saw those numbers dip below 50ms,
mostly hovering around 85-115ms."

If the range 50ms to 115ms is representative of two-way propagation
delays on their network, then it sounds like BBR can probably perform
reasonably well in that environment. The algorithm is designed to
tolerate factor-of-two variations in RTT and still maintain full
utilization, if there is reasonable buffering.

neal
_______________________________________________
Starlink mailing list
Starlin= k@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/starlink
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