Re: [tcpm] A description of Linux pacing

Martin Duke <martin.h.duke@gmail.com> Tue, 12 March 2024 22:08 UTC

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From: Martin Duke <martin.h.duke@gmail.com>
Date: Tue, 12 Mar 2024 15:08:09 -0700
Message-ID: <CAM4esxQg=MmBMJ-2dyWLX0HCy9yBCCaVBaWof31MFNBC-37ajQ@mail.gmail.com>
To: Michael Welzl <michawe@ifi.uio.no>
Cc: tcpm@ietf.org, iccrg@irtf.org
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Subject: Re: [tcpm] A description of Linux pacing
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Speaking as an individual, it's a bummer we don't have a real RFC about
pacing, this would be a decent Informational RFC for a way to do pacing,
that is also a useful reference for how an important implementation does it.

Even more ambitious, one could document the approaches of several major
implementations.

On Mon, Feb 19, 2024 at 6:06 AM Michael Welzl <michawe@ifi.uio.no> wrote:

> Dear TCPM and ICCRG (I assume that there’s so much overlap with people in
> CCWG that it would just be spamming to send it there too?),
>
> Over the last two weeks or so, I have put some effort into trying to
> understand how Linux pacing *really* works  (I had some descriptions that
> were somewhat high-level; I wanted to obtain a more precise lower-level
> understanding).
> I wrote a document, just for myself, explaining what goes on in the code,
> as I can’t even try to follow the Linux kernel without taking notes.
>
> After a first iteration, I shared it with the bufferbloat mailing list, in
> the hope of getting corrections.
> I did!  Most notably (but not only), Neal Cardwell helped me a ton - and
> now the document should be quite thorough and hopefully correct.
>
> While I only did this for myself and just asked the list for help, several
> people have in the meantime told me that this document is actually valuable
> for the community - and so I thought I should share it here, too.
> It lives as a Google doc at this URL:
>
> https://docs.google.com/document/d/1-uXnPDcVBKmg5krkG5wYBgaA2yLSFK_kZa7xGDWc7XU/edit?usp=sharing
>
> Comments or fixes are very welcome!
> Please feel free to forward this as you want.
>
> I know that Google docs is not the format that we people here normally use
>  :-)   well, if someone thinks that it would indeed be useful to write this
> up as an I-D (probably skipping all the code details though), please let me
> know - I can do that, and I can also present it if there’s interest (but in
> Vancouver, not Brisbane).
>
> Cheers,
> Michael
>
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