* can SFQ and perturb break paquet ordering ?
@ 2010-03-10 12:22 Julien Vehent
2010-03-10 12:30 ` Patrick McHardy
0 siblings, 1 reply; 2+ messages in thread
From: Julien Vehent @ 2010-03-10 12:22 UTC (permalink / raw)
To: netdev
Hi netdev folks,
I was digging into the sch_sfq code and I was wondering the following (I
assume it's nothing new, I'm just trying to get it right):
Let's consider one UDP connection that has two packets. Packet#1 goes to
bucket#1, then perturb modifies the hashing algorithms and thus Packet#2
goes to bucket#800.
If the round robin was positionned after bucket#1 but before bucket#800
when perturb occured, then Packet#2 will be sent before Packet#1. And since
UDP can't reordered, it will be processed before on the received end.
Am I getting this right or is there something in the code that I missed ?
Thanks for your help.
Julien Vehent
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: can SFQ and perturb break paquet ordering ?
2010-03-10 12:22 can SFQ and perturb break paquet ordering ? Julien Vehent
@ 2010-03-10 12:30 ` Patrick McHardy
0 siblings, 0 replies; 2+ messages in thread
From: Patrick McHardy @ 2010-03-10 12:30 UTC (permalink / raw)
To: Julien Vehent; +Cc: netdev
Julien Vehent wrote:
> Hi netdev folks,
>
> I was digging into the sch_sfq code and I was wondering the following (I
> assume it's nothing new, I'm just trying to get it right):
>
> Let's consider one UDP connection that has two packets. Packet#1 goes to
> bucket#1, then perturb modifies the hashing algorithms and thus Packet#2
> goes to bucket#800.
>
> If the round robin was positionned after bucket#1 but before bucket#800
> when perturb occured, then Packet#2 will be sent before Packet#1. And since
> UDP can't reordered, it will be processed before on the received end.
>
> Am I getting this right or is there something in the code that I missed ?
That's correct.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2010-03-10 12:30 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-03-10 12:22 can SFQ and perturb break paquet ordering ? Julien Vehent
2010-03-10 12:30 ` Patrick McHardy
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).