Re: [Patch net 08/12] selftests/tc-testing: Add a test case for CODEL with HTB parent

Cong Wang
2025-04-03T00:40:50Z

On Sun, Mar 30, 2025 at 4:32 PM Cong Wang <xiyou.wangcong@gmail.com> wrote:
>
> On Sun, Mar 30, 2025 at 06:05:06PM -0300, Victor Nogueira wrote:
> > On 28/03/2025 17:35, Cong Wang wrote:
> > > On Sun, Mar 23, 2025 at 07:48:39PM -0300, Victor Nogueira wrote:
> > > > On 20/03/2025 20:25, Cong Wang wrote:
> > > > > Add a test case for CODEL with HTB parent to verify packet drop
> > > > > behavior when the queue becomes empty. This helps ensure proper
> > > > > notification mechanisms between qdiscs.
> > > > >
> > > > > Note this is best-effort, it is hard to play with those parameters
> > > > > perfectly to always trigger ->qlen_notify().
> > > > >
> > > > > Cc: Pedro Tammela <pctammela@mojatatu.com>
> > > > > Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
> > > >
> > > > Cong, can you double check this test?
> > > > I ran all of your other tests and they all succeeded, however
> > > > this one specifically is always failing:
> > >
> > > Interesting, I thought I completely fixed this before posting after several
> > > rounds of playing with the parameters. I will double check it, maybe it
> > > just becomes less reproducible.
> >
> > I see.
> > I experimented with it a bit today and found out that changing the ping
> > command to:
> >
> > ping -c 2 -i 0 -s 1500 -I $DUMMY 10.10.10.1 > /dev/null || true
> >
> > makes the test pass consistently (at least in my environment).
> > So essentially just changing the "-s" option to 1500.
> >
> > If you could, please try it out as well.
> > Maybe I just got lucky.
>
> Sure, I will change it to 1500.

Hmm, it failed on my side:

Test a4bd: Test CODEL with HTB parent - force packet drop with empty queue

-----> prepare stage *** Could not execute: "ping -c 2 -i 0 -s 1500 -I
$DUMMY 10.10.10.1 > /dev/null || true"

-----> prepare stage *** Error message: "Command "/sbin/ip netns exec
tcut-3264298917 ping -c 2 -i 0 -s 1500 -I dummy1ida4bd 10.10.10.1 >
/dev/null || true" timed out
"
returncode 255; expected [0]