RE: rte_service unit test failing randomly

["Morten Brørup" <mb@smartsharesystems.com>]

+CC: DTS mailing list.

> From: David Marchand [mailto:david.marchand@redhat.com]
> Sent: Thursday, 6 October 2022 09.05
> 
> On Thu, Oct 6, 2022 at 8:53 AM Morten Brørup <mb@smartsharesystems.com>
> wrote:

[...]

> > Forgive me, if I am sidetracking a bit here... The issue discussed
> seems to be related to some threads waiting for other threads, and my
> question is not directly related to that.
> >
> > I have been wondering how accurate the tests really are. Where can I
> see what is being done to ensure that the EAL worker threads are fully
> isolated, and never interrupted by the O/S scheduler or similar?
> >
> > For reference, the max packet rate at 40 Gbit/s is 59.52 M pkt/s. If
> a NIC is configured with 4096 Rx descriptors, packet loss will occur
> after ca. 70 us (microseconds!) if not servicing the ingress queue when
> receiving at max packet rate.
> >
> > I recently posted some code for monitoring the O/S noise in EAL
> worker threads [1]. What should I do if I want to run that code in the
> automated test environment? It would be for informational purposes
> only, i.e. I would manually look at the test output to see the result.
> >
> > I would write a test application that simply starts the O/S noise
> monitor thread as an isolated EAL worker thread, the main thread would
> then wait for 10 minutes (or some other duration), dump the result to
> the standard output, and exit the application.
> >
> > [1]:
> http://inbox.dpdk.org/dev/98CBD80474FA8B44BF855DF32C47DC35D87352@smarts
> erver.smartshare.dk/
> 
> Maybe we could do some hack, like finding a test in the current CI
> that matches the test requirement: number of cores, ports, setup
> params etc... (retrieving the output could be another challenge).
> But if you think this is something we should have on the long run, I'd
> suggest writing a new DTS test.

It would be useful having in the long run - it could catch sudden anomalies in the test environment.

Where can I find documentation on how to add a new test case to DTS?

-Morten