<div dir="ltr">Hi Grenville,<div><br>Thanks for the email and the commit link!<br><br></div><div>Sorry for the late reply. I was traveling, and also going through the code which you shared.<br><br></div><div>I believe the implementation of FQ-PIE in FreeBSD matches the proposed ID very closely. I checked the code for the following:<br><br></div><div>1. There is a per queue PIE instance</div><div>2. Implementation of ECN support as described in Section 5.1 of RFC 8033 (<a href="https://datatracker.ietf.org/doc/html/rfc8033#section-5.1">https://datatracker.ietf.org/doc/html/rfc8033#section-5.1</a>)</div><div>3. Use timestamps as a default approach to calculate queue delay instead of Little's Law</div><div>4. The functionality of FQ to be similar to the one used in FQ-CoDel<br><br></div><div>and I found that all of the above are the same as mentioned in the ID. I'll edit the ID and mention this implementation. As of now, the ID mentions two implementations: Linux and ns-3.</div><div><br>Do you have any measurements performed with this implementation? or any other material related to this? I see it mentions that this is a beta implementation, but in case it was used in any real deployment or tested in live networks?<br><br></div><div>Thanks and Regards,</div><div>Mohit P. Tahiliani</div></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Tue, Mar 11, 2025 at 6:51 AM grenville armitage via Bloat <<a href="mailto:bloat@lists.bufferbloat.net">bloat@lists.bufferbloat.net</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u>
<div>
<div>Hi Mohit,<br>
<br>
I wonder what you think of the fq-pie developed for FreeBSD back
in 2015 and merged in May 2016? (commit <a href="https://reviews.freebsd.org/rS300779" target="_blank">here</a>.) It has
been too long since I last looked, so would love your thoughts on
how it aligns (or doesn't) with <a href="https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/" target="_blank">https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/</a>?<br>
<br>
cheers,<br>
gja<br>
<br>
On 2025-03-11 06:01, Mohit P. Tahiliani via Bloat wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">Hi all,<br>
<br>
I have been working on an Internet Draft on Flow Queue PIE
(FQ-PIE) [<a href="https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/" target="_blank">https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/</a>],
and recently submitted a revised version.<br>
<br>
It has been incorporated into the mainline Linux kernel as a
queuing discipline (qdisc). Additionally, an implementation of
FQ-PIE is available in the ns-3 network simulator.<br>
<br>
If you have any suggestions or feedback, please let me know.<br>
<br>
Thanks and Regards,<br>
Mohit P. Tahiliani<br>
<br>
<div class="gmail_quote">
<div dir="ltr" class="gmail_attr">---------- Forwarded message
---------<br>
From: <span dir="auto"><<a href="mailto:internet-drafts@ietf.org" target="_blank">internet-drafts@ietf.org</a>></span><br>
Date: Tue, Mar 4, 2025 at 12:56 AM<br>
Subject: New Version Notification for
draft-tahiliani-tsvwg-fq-pie-01.txt<br>
To: Mohit P. Tahiliani <<a href="mailto:tahiliani@nitk.edu.in" target="_blank">tahiliani@nitk.edu.in</a>><br>
</div>
<br>
<br>
A new version of Internet-Draft
draft-tahiliani-tsvwg-fq-pie-01.txt has been<br>
successfully submitted by Mohit Tahiliani and posted to the<br>
IETF repository.<br>
<br>
Name: draft-tahiliani-tsvwg-fq-pie<br>
Revision: 01<br>
Title: Flow Queue PIE: A Hybrid Packet Scheduler and Active
Queue Management Algorithm<br>
Date: 2025-03-03<br>
Group: Individual Submission<br>
Pages: 8<br>
URL: <a href="https://www.ietf.org/archive/id/draft-tahiliani-tsvwg-fq-pie-01.txt" rel="noreferrer" target="_blank">https://www.ietf.org/archive/id/draft-tahiliani-tsvwg-fq-pie-01.txt</a><br>
Status: <a href="https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/" rel="noreferrer" target="_blank">https://datatracker.ietf.org/doc/draft-tahiliani-tsvwg-fq-pie/</a><br>
HTML: <a href="https://www.ietf.org/archive/id/draft-tahiliani-tsvwg-fq-pie-01.html" rel="noreferrer" target="_blank">https://www.ietf.org/archive/id/draft-tahiliani-tsvwg-fq-pie-01.html</a><br>
HTMLized: <a href="https://datatracker.ietf.org/doc/html/draft-tahiliani-tsvwg-fq-pie" rel="noreferrer" target="_blank">https://datatracker.ietf.org/doc/html/draft-tahiliani-tsvwg-fq-pie</a><br>
Diff: <a href="https://author-tools.ietf.org/iddiff?url2=draft-tahiliani-tsvwg-fq-pie-01" rel="noreferrer" target="_blank">https://author-tools.ietf.org/iddiff?url2=draft-tahiliani-tsvwg-fq-pie-01</a><br>
<br>
Abstract:<br>
<br>
This document presents Flow Queue Proportional Integral
controller<br>
Enhanced (FQ-PIE), a hybrid packet scheduler and Active
Queue<br>
Management (AQM) algorithm to isolate flows and tackle the
problem of<br>
bufferbloat. FQ-PIE uses hashing to classify incoming
packets into<br>
different queues and provide flow isolation. Packets are
dequeued by<br>
using a variant of the round robin scheduler. Each such
flow is<br>
managed by the PIE algorithm to maintain high link
utilization while<br>
controlling the queue delay to a target value.<br>
<br>
<br>
<br>
The IETF Secretariat<br>
<br>
<br>
</div>
</div>
<br>
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