[PATCH i-g-t] tests/intel/xe_drm_fdinfo: Increase sampling period

[Cavitt, Jonathan]

-----Original Message-----
From: De Marchi, Lucas <lucas.demarchi at intel.com> 
Sent: Thursday, November 7, 2024 9:44 PM
To: igt-dev at lists.freedesktop.org
Cc: Cavitt, Jonathan <jonathan.cavitt at intel.com>; Nerlige Ramappa, Umesh <umesh.nerlige.ramappa at intel.com>; Brost, Matthew <matthew.brost at intel.com>; De Marchi, Lucas <lucas.demarchi at intel.com>
Subject: [PATCH i-g-t] tests/intel/xe_drm_fdinfo: Increase sampling period
> 
> This reverts commit 4f79f059766c ("tests/intel/xe_drm_fdinfo: Half the
> execution time") and goes in the opposite direction, doubling it.
> Although in some machines we pass consistently, others like LNL
> show sporadic failures.
> 
> Even after changes in the kernel to improve it, it still shows those
> failures. Also, the failures can be much more frequent by stressing all
> the CPUs. Raise the period to reduce the error introduced due to
> additional scheduling delays. This shows a good improvement on LNL that
> doesn't fail anymore without CPU load and fails once every ~200
> iterations with 100% CPU load (vs once every ~3 iterations).
> 
> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>

LGTM
Reviewed-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
-Jonathan Cavitt

> ---
>  tests/intel/xe_drm_fdinfo.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tests/intel/xe_drm_fdinfo.c b/tests/intel/xe_drm_fdinfo.c
> index 5fd7c0416..ef9273e2a 100644
> --- a/tests/intel/xe_drm_fdinfo.c
> +++ b/tests/intel/xe_drm_fdinfo.c
> @@ -82,7 +82,7 @@ struct pceu_cycles {
>  	uint64_t total_cycles;
>  };
>  
> -const unsigned long batch_duration_usec = (1 * USEC_PER_SEC) / 4;
> +const unsigned long batch_duration_usec = (1 * USEC_PER_SEC);
>  
>  static const char *engine_map[] = {
>  	"rcs",
> -- 
> 2.47.0
> 
>