Le jeudi 27 octobre 2011 à 14:46 +0200, Karel Rericha a écrit :

Actually I am doing some reseach to replace our main shaping machine
with 60 000+ htb classes, which now saturates 12 core Xeon Westmere to
30% (there are five gigabit network ports on each interface affinited
to cores). AFAIK QFQ should be O(1) complexity so it would bring
saturation a requirements for number of cores down considerably (HTB
has O(log(N)) complexity).

I have test machine and about two months to decide if we will stay
with HTB or we will try something else. So it would be VERY helpful,
if you would search you memory instead your dead disk :-) and send me
some example of QFQ usage, if I can ask for a little of your time. I
promise to have results published here in return.

Thanks, Karel

That seems a good challenge to me ;)

First upgrade to a recent kernel with QFQ included.
Also upgrade iproute2 to a recent enough version as well.

Then you discover "tc  ... qfq help" is not that helpful :(

# tc qdisc add dev eth3 root qfq help
Usage: ... qfq

OK, its parameters are :

	qfq weight num1 [maxpkt BYTES]

You should not touch maxpkt, its default value being 2048

Oh well, I just tried the obvious and my (remote) machine doesnt answer
to me anymore...

Time for a bit of debugging I am afraid :(