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

[Victor Nogueira <victor@mojatatu.com>]

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.

cheers,
Victor