To my understanding a proper operating AQM _is_ work-conserving. Packet drops 
occur, if any, when a reasonable queue is present. And as long as packets are 
present in the queue, the link runs at 100%. I cannot see any (AQM) mechanism 
that is holding back queued packets while the link is idle.

Wolfram


From: aqm [mailto:[email protected]] On Behalf Of Rong Pan (ropan)
Sent: Dienstag, 28. März 2017 16:17
To: Luca Muscariello <[email protected]>; Bless, Roland (TM) 
<[email protected]>
Cc: tsvwg IETF list <[email protected]>; Fred Baker <[email protected]>; 
Bob Briscoe <[email protected]>; De Schepper, Koen (Nokia - BE/Antwerp) 
<[email protected]>; Greg White <[email protected]>; 
Jonathan Morton <[email protected]>; AQM IETF list <[email protected]>; Preethi 
Natarajan <[email protected]>
Subject: Re: [aqm] Questioning each PIE heuristic

Sorry for causing the confusion in choosing the word "work-conserving". If we 
apply AQM and can not achieving 100% line rate, i.e. losing throughput, it is a 
big No No. Since we are dealing with TCP traffic, excess drops can cause TCP to 
back off too much and under-utilize the link.

Rong

From: Luca Muscariello 
<[email protected]<mailto:[email protected]>>
Date: Tuesday, March 28, 2017 at 8:48 AM
To: "Bless, Roland (TM)" <[email protected]<mailto:[email protected]>>
Cc: Fred Baker <[email protected]<mailto:[email protected]>>, 
Jonathan Morton <[email protected]<mailto:[email protected]>>, tsvwg 
IETF list <[email protected]<mailto:[email protected]>>, Bob Briscoe 
<[email protected]<mailto:[email protected]>>, "De Schepper, Koen (Koen)" 
<[email protected]<mailto:[email protected]>>, Rong Pan 
<[email protected]<mailto:[email protected]>>, Greg White 
<[email protected]<mailto:[email protected]>>, AQM IETF list 
<[email protected]<mailto:[email protected]>>, Preethi Natarajan 
<[email protected]<mailto:[email protected]>>
Subject: Re: [aqm] Questioning each PIE heuristic

Work conserving is supposed to be referring to the scheduler.
I'm not familiar with work-conservation when it refers to active queue 
management.
I'm not sure it is actually defined.

I can understand that an AQM can produce under utilization of the link, but 
that is
different to work conservation. Or is it maybe more subtle than that?

Luca

On Tue, Mar 28, 2017 at 1:48 PM, Bless, Roland (TM) 
<[email protected]<mailto:[email protected]>> wrote:
Hi,

Am 28.03.2017 um 13:39 schrieb Fred Baker:

> I'm not convinced I understand the definitions of "work conserving"
> and "non work conserving" in this context. A "work conserving"
> scheduling algorithm keeps an interface transmitting as long as there
> is data in the queue, while a non-work-conserving algorithm reduces
> the effective rate of the interface by spacing packets out.

+1 (that's also the definition I use, so I'm lost here too)

Regards,
 Roland

_______________________________________________
aqm mailing list
[email protected]<mailto:[email protected]>
https://www.ietf.org/mailman/listinfo/aqm

_______________________________________________
aqm mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/aqm

Reply via email to