[igt-dev] [PATCH i-g-t] tests/perf: add a test for OA data polling reads using "small" buffers

[Lionel Landwerlin]

On 27/03/2020 21:03, Dixit, Ashutosh wrote:
> On Fri, 27 Mar 2020 09:09:41 -0700, Lionel Landwerlin wrote:
>> On 27/03/2020 06:50, Dixit, Ashutosh wrote:
>>> On Thu, 26 Mar 2020 21:42:50 -0700, Ashutosh Dixit wrote:
>>>> diff --git a/tests/perf.c b/tests/perf.c
>>>> index 724f6f809..3dc757c3b 100644
>>>> --- a/tests/perf.c
>>>> +++ b/tests/perf.c
>>>> +static void test_polling_small_buf(void)
>>>> +{
>>> /snip/
>>>
>>>> +
>>>> +	igt_assert(abs(n_expect_read_bytes - n_bytes_read) < (0.10 * n_expect_read_bytes));
>>>> +}
>>>> +
>>> I'd be wary of a 90% match on slow platforms like Atom? Maybe 80% is safer?
>>
>> Do we have any experiment showing them behaving differently?
> No I don't have any data, but considering that in previous stable versions
> we can only read < 10% of the data, I think it should be ok to go down to
> 80%? So that we don't start getting unnecessary false alarms in CI, even
> when the issue is fixed.

Okay, for the record I get somewhere between 93~95% of expected reports 
on KBLGT2.


-Lionel