Re: [PATCH] tests/qtest/npcm7xx_watchdog_timer: Only test the corner cases by default

[Alex Bennée]

Thomas Huth <thuth@redhat.com> writes:

> On 15/01/2024 12.32, Alex Bennée wrote:
>> Thomas Huth <thuth@redhat.com> writes:
>> 
>>> The test_prescaler() part in the npcm7xx_watchdog_timer test is quite
>>> repetive, testing all possible combinations of the WTCLK and WTIS
>>> bitfields. Since each test spins up a new instance of QEMU, this is
>>> rather an expensive test, especially on loaded host systems.
>> I'm not against the change but I do not my home machine runs these
>> tests
>> in:
>>    1/1 qemu:qtest+qtest-arm / qtest-arm/npcm7xx_timer-test        OK
>> 0.18s   180 subtests passed
>
> That's a different test, I think. Look for "watchdog" in its name,
> please.

Ahh -ETOOMANYNPCMS...

So yes I get a drop in time by half:

  1/1 qemu:qtest+qtest-arm / qtest-arm/npcm7xx_watchdog_timer-test        OK    
         10.35s   15 subtests passed

to

  1/1 qemu:qtest+qtest-arm / qtest-arm/npcm7xx_watchdog_timer-test        OK    
          4.68s   15 subtests passed


Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

>> so I do wonder how the system load can cause such a dramatic increase
>> for a comparatively simple test.
>
> The watchdog test is executing a new QEMU instance for each test in
> the loop, and that can be quite expensive on a loaded system, I think.
>
>  Thomas

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro