The initial value of 5% chosen for the maximum allowed percentage difference between resctrl mbm value and IMC mbm value in commit 06bd03a57f8c ("selftests/resctrl: Fix MBA/MBM results reporting format") was "randomly chosen value" (as admitted by the changelog).
When running tests in our lab across a large number platforms, 5% difference upper bound for success seems a bit on the low side for the MBA and MBM tests. Some platforms produce outliers that are slightly above that, typically 6-7%, which leads MBA/MBM test frequently failing.
Replace the "randomly chosen value" with a success bound that is based on those measurements across large number of platforms by relaxing the MBA/MBM success bound to 8%. The relaxed bound removes the failures due the frequent outliers.
Fixes: 06bd03a57f8c ("selftests/resctrl: Fix MBA/MBM results reporting format") Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Tested-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Reviewed-by: Reinette Chatre reinette.chatre@intel.com Reviewed-by: Shaopeng Tan tan.shaopeng@jp.fujitsu.com Cc: stable@vger.kernel.org --- tools/testing/selftests/resctrl/mba_test.c | 2 +- tools/testing/selftests/resctrl/mbm_test.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/testing/selftests/resctrl/mba_test.c b/tools/testing/selftests/resctrl/mba_test.c index cf8284dadcb2..d3bf4368341e 100644 --- a/tools/testing/selftests/resctrl/mba_test.c +++ b/tools/testing/selftests/resctrl/mba_test.c @@ -12,7 +12,7 @@
#define RESULT_FILE_NAME "result_mba" #define NUM_OF_RUNS 5 -#define MAX_DIFF_PERCENT 5 +#define MAX_DIFF_PERCENT 8 #define ALLOCATION_MAX 100 #define ALLOCATION_MIN 10 #define ALLOCATION_STEP 10 diff --git a/tools/testing/selftests/resctrl/mbm_test.c b/tools/testing/selftests/resctrl/mbm_test.c index 1ae131a2e246..d3c0d30c676a 100644 --- a/tools/testing/selftests/resctrl/mbm_test.c +++ b/tools/testing/selftests/resctrl/mbm_test.c @@ -11,7 +11,7 @@ #include "resctrl.h"
#define RESULT_FILE_NAME "result_mbm" -#define MAX_DIFF_PERCENT 5 +#define MAX_DIFF_PERCENT 8 #define NUM_OF_RUNS 5
static int