Re: [tcpm] [EXTERNAL] Re: Changes to draft-ietf-tcpm-hystartplusplus after WGLC

[Yi Huang <[e-mail]>]

Thanks for the review. We will fix the text.
________________________________
From: tcpm <[e-mail]> on behalf of Neal Cardwell <ncardwell=[e-mail]>
Sent: Tuesday, November 29, 2022 10:31 AM
To: [e-mail] <[e-mail]>
Cc: tcpm <[e-mail]>; [e-mail] <[e-mail]>
Subject: [EXTERNAL] Re: [tcpm] Changes to draft-ietf-tcpm-hystartplusplus after WGLC

On Tue, Nov 29, 2022 at 7:05 AM <[e-mail]<mailto:[e-mail]>> wrote:
Dear all,

during the AD review, some changes have been made to draft-ietf-tcpm-hystartplusplus-09
in relation with RFC 3465 (TCP Congestion Control with Appropriate Byte Counting (ABC))
to avoid referencing an informational document from a standards track document.

These changes can be reviewed using:
https://www.ietf.org/rfcdiff?url1=https://www.ietf.org/archive/id/draft-ietf-tcpm-hystartplusplus-09.txt&url2=https://www.ietf.org/archive/id/draft-ietf-tcpm-hystartplusplus-11.txt<https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ietf.org%2Frfcdiff%3Furl1%3Dhttps%3A%2F%2Fwww.ietf.org%2Farchive%2Fid%2Fdraft-ietf-tcpm-hystartplusplus-09.txt%26url2%3Dhttps%3A%2F%2Fwww.ietf.org%2Farchive%2Fid%2Fdraft-ietf-tcpm-hystartplusplus-11.txt&data=05%7C01%7Chuanyi%40microsoft.com%7C4d696c111df64eb2140b08dad2380a46%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C638053436298570898%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=pD04rA034qVHHhu8S1V2EeeRu9QP8rttCNToSD5stUc%3D&reserved=0>

Please indicate within a week, whether you are fine with these changes or provide
some comments.

Thanks for posting the diff!

Regarding this part of section 5, "Deployments and Performance Evaluations":


   The original Hystart has been default-enabled
   for all TCP connections in the Linux operating system using the
   default congestion control module CUBIC ([RFC8312]) for a decade with
   L = infinity with pacing enabled.

The "with pacing enabled" part looks inaccurate. Linux TCP thus far has not enabled pacing by default. This passage would be correct if modified to read: "for a decade with L = infinity with pacing disabled by default."

To be clear, the algorithm variant mentioned here (Linux TCP with CUBIC Hystart and L=infinity and pacing enabled) has had plenty of air miles, including YouTube and Google TCP traffic in the 2013-2016 era. But the "pacing enabled" part is only true of Linux installations that use the "fq" qdisc, which is not the default for the Linux kernel or any major Linux distribution that I'm aware of ("fq_codel" is increasingly common among major Linux distributions, but it does not implement pacing).

The rest of the update looks good to me.

Thanks!

best regards,
neal


Best regards
Michael_______________________________________________
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