diff --git a/app/vmselect/promql/rollup.go b/app/vmselect/promql/rollup.go index 247743ddc5..c711f04ad8 100644 --- a/app/vmselect/promql/rollup.go +++ b/app/vmselect/promql/rollup.go @@ -338,9 +338,12 @@ type rollupFuncArg struct { // Timestamps for values. timestamps []int64 - // Actual value preceeding values without restrictions on staleness interval. + // Real value preceeding values without restrictions on staleness interval. realPrevValue float64 + // Real value which goes after values. + realNextValue float64 + // Current timestamp for rollup evaluation. currTimestamp int64 @@ -558,6 +561,11 @@ func (rc *rollupConfig) doInternal(dstValues []float64, tsm *timeseriesMap, valu } else { rfa.realPrevValue = nan } + if j < len(values) { + rfa.realNextValue = values[j] + } else { + rfa.realNextValue = nan + } rfa.currTimestamp = tEnd value := rc.Func(rfa) rfa.idx++ @@ -1282,6 +1290,8 @@ func rollupDelta(rfa *rollupFuncArg) float64 { d := float64(10) if len(values) > 1 { d = values[1] - values[0] + } else if !math.IsNaN(rfa.realNextValue) { + d = rfa.realNextValue - values[0] } if math.Abs(values[0]) < 10*(math.Abs(d)+1) { prevValue = 0 diff --git a/app/vmselect/promql/rollup_test.go b/app/vmselect/promql/rollup_test.go index e0eaacb6cd..dff89e2c8e 100644 --- a/app/vmselect/promql/rollup_test.go +++ b/app/vmselect/promql/rollup_test.go @@ -1103,12 +1103,13 @@ func testRowsEqual(t *testing.T, values []float64, timestamps []int64, valuesExp } func TestRollupDelta(t *testing.T) { - f := func(prevValue, realPrevValue float64, values []float64, resultExpected float64) { + f := func(prevValue, realPrevValue, realNextValue float64, values []float64, resultExpected float64) { t.Helper() rfa := &rollupFuncArg{ prevValue: prevValue, values: values, realPrevValue: realPrevValue, + realNextValue: realNextValue, } result := rollupDelta(rfa) if math.IsNaN(result) { @@ -1121,26 +1122,36 @@ func TestRollupDelta(t *testing.T) { t.Fatalf("unexpected result; got %v; want %v", result, resultExpected) } } - f(nan, nan, nil, nan) + f(nan, nan, nan, nil, nan) // Small initial value - f(nan, nan, []float64{1}, 1) - f(nan, nan, []float64{10}, 10) - f(nan, nan, []float64{100}, 100) - f(nan, nan, []float64{1, 2, 3}, 3) - f(1, nan, []float64{1, 2, 3}, 2) - f(nan, nan, []float64{5, 6, 8}, 8) - f(2, nan, []float64{5, 6, 8}, 6) + f(nan, nan, nan, []float64{1}, 1) + f(nan, nan, nan, []float64{10}, 10) + f(nan, nan, nan, []float64{100}, 100) + f(nan, nan, nan, []float64{1, 2, 3}, 3) + f(1, nan, nan, []float64{1, 2, 3}, 2) + f(nan, nan, nan, []float64{5, 6, 8}, 8) + f(2, nan, nan, []float64{5, 6, 8}, 6) // Too big initial value must be skipped. - f(nan, nan, []float64{1000}, 0) - f(nan, nan, []float64{1000, 1001, 1002}, 2) + f(nan, nan, nan, []float64{1000}, 0) + f(nan, nan, nan, []float64{1000, 1001, 1002}, 2) - // Delta calculations against non-nan realPrevValue - f(nan, 900, []float64{1000}, 100) - f(nan, 900, []float64{1000, 1001, 1002}, 102) + // Non-nan realPrevValue + f(nan, 900, nan, []float64{1000}, 100) + f(nan, 1000, nan, []float64{1000}, 0) + f(nan, 1100, nan, []float64{1000}, -100) + f(nan, 900, nan, []float64{1000, 1001, 1002}, 102) + + // Small delta between realNextValue and values + f(nan, nan, 990, []float64{1000}, 0) + f(nan, nan, 1005, []float64{1000}, 0) + + // Big delta between relaNextValue and values + f(nan, nan, 800, []float64{1000}, 1000) + f(nan, nan, 1300, []float64{1000}, 1000) // Empty values - f(1, nan, nil, 0) - f(100, nan, nil, 0) + f(1, nan, nan, nil, 0) + f(100, nan, nan, nil, 0) }