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From: Michael Welzl <michawe@ifi.uio.no>
To: bloat@lists.bufferbloat.net
Subject: [Bloat] Trying to *really* understand Linux pacing
Date: Wed, 7 Feb 2024 12:56:59 +0100	[thread overview]
Message-ID: <1BAA689A-D44E-4122-9AD8-25F6D024377E@ifi.uio.no> (raw)

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Dear de-bloaters of buffers,
Esteemed experts of low delay and pacing!

I have no longer been satisfied with high-level descriptions of how pacing works in Linux, and how it interacts with TSQ (I’ve seen some, in various papers, over the years) - but I wanted to REALLY understand it. So, I have dug through the code.

I documented this experience here:
https://docs.google.com/document/d/1-uXnPDcVBKmg5krkG5wYBgaA2yLSFK_kZa7xGDWc7XU/edit?usp=sharing <https://docs.google.com/document/d/1-uXnPDcVBKmg5krkG5wYBgaA2yLSFK_kZa7xGDWc7XU/edit?usp=sharing>
but it has some holes and may have mistakes.

Actually, my main problem is that I don’t really know what goes on when I configure a larger IW… things seem to get quite “off” there. Why? Anyone up for solving that riddle?  ;-)
(see the tests I documented towards the end of the document)

Generally, if someone who has their hands on files such as tcp_output.c all the time could take a look, and perhaps “fill” my holes, or improve anything that might be wrong, that would be fantastic!   I think that anyone should be allowed to comment and make suggestions in this doc.

MANY thanks to whoever finds the time to take a look !

Cheers,
Michael


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             reply	other threads:[~2024-02-07 11:57 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-02-07 11:56 Michael Welzl [this message]
2024-02-07 12:05 ` Dave Taht
2024-02-07 12:08   ` Michael Welzl
2024-02-07 12:20     ` Dave Taht
2024-02-07 20:13       ` Neal Cardwell
2024-02-19 13:54         ` Michael Welzl
2024-02-19 14:02           ` Dave Taht
2024-02-07 15:03   ` Stephen Hemminger

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