TRT-2487: job-run-aggregator: remove relaxing in disruption aggregation

I do not _entirely_ understand why the relaxation for disruption tests
exists here but the TODO exists this may be worth tightening. The
`pityFactor` will relax the threshold in some cases (high attempts,
high pass rate) so the additional relaxation would only apply in the
remaining cases.

Author: petr-muller

pkg/jobrunaggregator/jobrunaggregatoranalyzer/pass_fail.go

@@ -490,12 +490,6 @@ func (a *weeklyAverageFromTenDays) innerCheckPercentileDisruptionWithGrace(
 	strictRequiredNumberOfPasses := requiredPassesByPassPercentageByNumberOfAttempts[numberOfAttempts][workingPercentage]
 	requiredNumberOfPasses, pityFactorMsg := pityFactor(numberOfAttempts, strictRequiredNumberOfPasses)
 
-	if requiredNumberOfPasses == strictRequiredNumberOfPasses {
-		// TODO try to tighten this after we can keep the test in for about a week.
-		// We need to come back and revisit the possibility of removing this adjustment.
-		requiredNumberOfPasses = requiredNumberOfPasses - 1 // subtracting one because our current sample missed by one
-	}
-
 	if requiredNumberOfPasses <= 0 {
 		message := fmt.Sprintf("Current percentile is so low that we cannot latch, skipping (P%d=%.2fs successes=%v failures=%v)", thresholdPercentile, threshold, successRuns, failureRuns)
 		failureJobRunIDs = sets.StringKeySet(jobRunIDToAvailabilityResultForBackend).List()

pkg/jobrunaggregator/jobrunaggregatoranalyzer/pass_fail_test.go

@@ -500,16 +500,15 @@ func TestInnerCheckPercentileDisruptionWithPityFactor(t *testing.T) {
 	}{
 		// Note: In innerCheckPercentileDisruptionWithGrace, workingPercentage = thresholdPercentile
 		// So a P95 test uses 95% as the working percentage for calculating required passes
-		// The code also has -1 adjustment when pity factor doesn't relax the requirement
 		{
 			name:                 "10 attempts, P95 (95% working): 8 passes, 2 failures - exceeds requirement",
 			disruptions:          []int{0, 0, 0, 1, 1, 1, 1, 1, 5, 5},
 			thresholdPercentile:  95,
 			historicalDisruption: 2.0,
 			graceSeconds:         0,
 			expectedStatus:       testCasePassed,
-			expectedMinPasses:    6, // strict=7, pity=min(10-2,7)=7, then 7-1=6 (no relaxation)
-			description:          "Strict=7, pity=min(10-2,7)=7, -1 adj=6. 8 passes exceeds requirement",
+			expectedMinPasses:    7, // strict=7, pity=min(10-2,7)=7 (no relaxation)
+			description:          "Strict=7, pity=min(10-2,7)=7. 8 passes exceeds requirement",
 		},
 		{
 			name:                 "10 attempts, P95 (95% working): 7 passes, 3 failures - meets requirement",
@@ -518,8 +517,8 @@ func TestInnerCheckPercentileDisruptionWithPityFactor(t *testing.T) {
 			historicalDisruption: 2.0,
 			graceSeconds:         0,
 			expectedStatus:       testCasePassed,
-			expectedMinPasses:    6, // strict=7, pity=min(10-2,7)=7, then 7-1=6 (no relaxation)
-			description:          "Strict=7, pity=min(10-2,7)=7, -1 adj=6. 7 passes exceeds requirement",
+			expectedMinPasses:    7, // strict=7, pity=min(10-2,7)=7 (no relaxation)
+			description:          "Strict=7, pity=min(10-2,7)=7. 7 passes meets requirement exactly",
 		},
 		{
 			name:                 "6 attempts, P80 (80% working): 4 passes, 2 failures - exceeds requirement",
@@ -528,8 +527,8 @@ func TestInnerCheckPercentileDisruptionWithPityFactor(t *testing.T) {
 			historicalDisruption: 2.0,
 			graceSeconds:         0,
 			expectedStatus:       testCasePassed,
-			expectedMinPasses:    1, // strict=2, pity=min(6-2,2)=2, then 2-1=1 (no relaxation)
-			description:          "Strict=2, pity=min(6-2,2)=2, -1 adj=1. 4 passes exceeds requirement",
+			expectedMinPasses:    2, // strict=2, pity=min(6-2,2)=2 (no relaxation)
+			description:          "Strict=2, pity=min(6-2,2)=2. 4 passes exceeds requirement",
 		},
 		{
 			name:                 "12 attempts, P95 (95% working): 10 passes, 2 failures - exceeds requirement",
@@ -538,8 +537,8 @@ func TestInnerCheckPercentileDisruptionWithPityFactor(t *testing.T) {
 			historicalDisruption: 2.0,
 			graceSeconds:         0,
 			expectedStatus:       testCasePassed,
-			expectedMinPasses:    8, // strict=9, pity=min(12-2,9)=9, then 9-1=8 (no relaxation)
-			description:          "Strict=9, pity=min(12-2,9)=9, -1 adj=8. 10 passes exceeds requirement",
+			expectedMinPasses:    9, // strict=9, pity=min(12-2,9)=9 (no relaxation)
+			description:          "Strict=9, pity=min(12-2,9)=9. 10 passes exceeds requirement",
 		},
 	}