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

[Dixit, Ashutosh]

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.