Re: [PATCH 03/10] tests/avocado/intel_iommu.py: increase timeout

[Alex Bennée]

Eric Auger <eric.auger@redhat.com> writes:

> Hi Cleber,
>
> On 12/13/23 21:08, Cleber Rosa wrote:
>> Alex Bennée <alex.bennee@linaro.org> writes:
>>
>>> Cleber Rosa <crosa@redhat.com> writes:
>>>
>>>> Based on many runs, the average run time for these 4 tests is around
>>>> 250 seconds, with 320 seconds being the ceiling.  In any way, the
>>>> default 120 seconds timeout is inappropriate in my experience.
>>> I would rather see these tests updated to fix:
>>>
>>>  - Don't use such an old Fedora 31 image
>> I remember proposing a bump in Fedora version used by default in
>> avocado_qemu.LinuxTest (which would propagate to tests such as
>> boot_linux.py and others), but that was not well accepted.  I can
>> definitely work on such a version bump again.
>>
>>>  - Avoid updating image packages (when will RH stop serving them?)
>> IIUC the only reason for updating the packages is to test the network
>> from the guest, and could/should be done another way.
>>
>> Eric, could you confirm this?
> Sorry for the delay. Yes effectively I used the dnf install to stress
> the viommu. In the past I was able to trigger viommu bugs that way
> whereas getting an IP @ for the guest was just successful.
>>
>>>  - The "test" is a fairly basic check of dmesg/sysfs output
>> Maybe the network is also an implicit check here.  Let's see what Eric
>> has to say.
>
> To be honest I do not remember how avocado does the check in itself; my
> guess if that if the dnf install does not complete you get a timeout and
> the test fails. But you may be more knowledged on this than me ;-)

I guess the problem is relying on external infrastructure can lead to
unpredictable results. However its a lot easier to configure user mode
networking just to pull something off the internet than have a local
netperf or some such setup to generate local traffic.

I guess there is no loopback like setup which would sufficiently
exercise the code?

>
> Thanks
>
> Eric
>>
>>> I think building a buildroot image with the tools pre-installed (with
>>> perhaps more testing) would be a better use of our limited test time.
>>>
>>> FWIW the runtime on my machine is:
>>>
>>> ➜  env QEMU_TEST_FLAKY_TESTS=1 ./pyvenv/bin/avocado run 
>>> ./tests/avocado/intel_iommu.py
>>> JOB ID     : 5c582ccf274f3aee279c2208f969a7af8ceb9943
>>> JOB LOG    : 
>>> /home/alex/avocado/job-results/job-2023-12-11T16.53-5c582cc/job.log
>>>  (1/4) ./tests/avocado/intel_iommu.py:IntelIOMMU.test_intel_iommu: PASS 
>>> (44.21 s)
>>>  (2/4) ./tests/avocado/intel_iommu.py:IntelIOMMU.test_intel_iommu_strict: 
>>> PASS (78.60 s)
>>>  (3/4) 
>>> ./tests/avocado/intel_iommu.py:IntelIOMMU.test_intel_iommu_strict_cm: PASS 
>>> (65.57 s)
>>>  (4/4) ./tests/avocado/intel_iommu.py:IntelIOMMU.test_intel_iommu_pt: PASS 
>>> (66.63 s)
>>> RESULTS    : PASS 4 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | 
>>> CANCEL 0
>>> JOB TIME   : 255.43 s
>>>
>> Yes, I've also seen similar runtimes in other environments... so it
>> looks like it depends a lot on the "dnf -y install numactl-devel".  If
>> that can be removed, the tests would have much more predictable runtimes.
>>

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro