On 16-01-06 05:14 AM, Jamal Hadi Salim wrote:

Sorry for not being as responsive as i would like to be
(theman calls and i have to go).
This looks like a good (tc workshop) candidate discussion, if still
active by netdev11 time.

On 15-12-30 12:50 PM, John Fastabend wrote:

quoted

Hi,

This is a first take at removing the qdisc lock on the xmit path
where qdiscs actually have queues of skbs. The ingress qdisc
which is already lockless was "easy" at least in the sense that
we did not need any lock-free data structures to hold skbs.

I did some testing over the holidays for a netdev11 paper submission
and the ingress qdisc side of things looks very impressive (on
an average packet size) on a single (i7 class) cpu.
It can handle about 3x what an egress side pktgen type test (not
very real life) can handle. Analysis shows the lock is killing us.
So if you are looking at low hanging fruit, the egress is
the place to look.

So this series drops the qdisc lock which should hopefully per
some older data I have bring it on par with the ingress side. But
I need to retest this latest patch series.

I have a pktgen change that may be useful for you - I will post
it next time i get cycles.
I am also a willing guinea pig (given upcoming netdev11) to do
some perf testing ;->

I typically test this by putting vlan's on top of a dev with the
qdisc I want to test and running pktgen on the vlans the entry point
of the skb is pretty much where I want it in this case.

cheers,
jamal