promql: rename holt_winters to double_exponential_smoothing

jan--f · jan--f · commit 96e5a94d2970 · 2024-09-19T15:29:01.000+02:00
Signed-off-by: Jan Fajerski &lt;jfajersk@redhat.com&gt;
diff --git a/docs/querying/functions.md b/docs/querying/functions.md
@@ -380,17 +380,22 @@ do not show up in the returned vector.
 Similarly, `histogram_stdvar(v instant-vector)` returns the estimated standard
 variance of observations in a native histogram.
 
-## `holt_winters()`
+## `double_exponential_smoothing()`
 
 **This function has to be enabled via the [feature flag](../feature_flags.md#experimental-promql-functions) `--enable-feature=promql-experimental-functions`.**
 
-`holt_winters(v range-vector, sf scalar, tf scalar)` produces a smoothed value
+`double_exponential_smoothing(v range-vector, sf scalar, tf scalar)` produces a smoothed value
 for time series based on the range in `v`. The lower the smoothing factor `sf`,
 the more importance is given to old data. The higher the trend factor `tf`, the
 more trends in the data is considered. Both `sf` and `tf` must be between 0 and
 1.
+For additional details, refer to [NIST Engineering Statistics Handbook](https://www.itl.nist.gov/div898/handbook/pmc/section4/pmc433.htm).
+In Prometheus V2 this function was called `holt_winters`. This caused confusion
+since the Holt-Winters method usually refers to triple exponential smoothing.
+Double exponential smoothing as implemented here is also referred to as "Holt
+Linear".
 
-`holt_winters` should only be used with gauges.
+`double_exponential_smoothing` should only be used with gauges.
 
 ## `hour()`
 
diff --git a/promql/bench_test.go b/promql/bench_test.go
@@ -117,7 +117,7 @@ func rangeQueryCases() []benchCase {
 		},
 		// Holt-Winters and long ranges.
 		{
-			expr: "holt_winters(a_X[1d], 0.3, 0.3)",
+			expr: "double_exponential_smoothing(a_X[1d], 0.3, 0.3)",
 		},
 		{
 			expr: "changes(a_X[1d])",
diff --git a/promql/functions.go b/promql/functions.go
@@ -350,7 +350,7 @@ func calcTrendValue(i int, tf, s0, s1, b float64) float64 {
 // data. A lower smoothing factor increases the influence of historical data. The trend factor (0 < tf < 1) affects
 // how trends in historical data will affect the current data. A higher trend factor increases the influence.
 // of trends. Algorithm taken from https://en.wikipedia.org/wiki/Exponential_smoothing titled: "Double exponential smoothing".
-func funcHoltWinters(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+func funcDoubleExponentialSmoothing(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	samples := vals[0].(Matrix)[0]
 
 	// The smoothing factor argument.
@@ -1657,82 +1657,82 @@ func funcYear(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper)
 
 // FunctionCalls is a list of all functions supported by PromQL, including their types.
 var FunctionCalls = map[string]FunctionCall{
-	"abs":                funcAbs,
-	"absent":             funcAbsent,
-	"absent_over_time":   funcAbsentOverTime,
-	"acos":               funcAcos,
-	"acosh":              funcAcosh,
-	"asin":               funcAsin,
-	"asinh":              funcAsinh,
-	"atan":               funcAtan,
-	"atanh":              funcAtanh,
-	"avg_over_time":      funcAvgOverTime,
-	"ceil":               funcCeil,
-	"changes":            funcChanges,
-	"clamp":              funcClamp,
-	"clamp_max":          funcClampMax,
-	"clamp_min":          funcClampMin,
-	"cos":                funcCos,
-	"cosh":               funcCosh,
-	"count_over_time":    funcCountOverTime,
-	"days_in_month":      funcDaysInMonth,
-	"day_of_month":       funcDayOfMonth,
-	"day_of_week":        funcDayOfWeek,
-	"day_of_year":        funcDayOfYear,
-	"deg":                funcDeg,
-	"delta":              funcDelta,
-	"deriv":              funcDeriv,
-	"exp":                funcExp,
-	"floor":              funcFloor,
-	"histogram_avg":      funcHistogramAvg,
-	"histogram_count":    funcHistogramCount,
-	"histogram_fraction": funcHistogramFraction,
-	"histogram_quantile": funcHistogramQuantile,
-	"histogram_sum":      funcHistogramSum,
-	"histogram_stddev":   funcHistogramStdDev,
-	"histogram_stdvar":   funcHistogramStdVar,
-	"holt_winters":       funcHoltWinters,
-	"hour":               funcHour,
-	"idelta":             funcIdelta,
-	"increase":           funcIncrease,
-	"irate":              funcIrate,
-	"label_replace":      funcLabelReplace,
-	"label_join":         funcLabelJoin,
-	"ln":                 funcLn,
-	"log10":              funcLog10,
-	"log2":               funcLog2,
-	"last_over_time":     funcLastOverTime,
-	"mad_over_time":      funcMadOverTime,
-	"max_over_time":      funcMaxOverTime,
-	"min_over_time":      funcMinOverTime,
-	"minute":             funcMinute,
-	"month":              funcMonth,
-	"pi":                 funcPi,
-	"predict_linear":     funcPredictLinear,
-	"present_over_time":  funcPresentOverTime,
-	"quantile_over_time": funcQuantileOverTime,
-	"rad":                funcRad,
-	"rate":               funcRate,
-	"resets":             funcResets,
-	"round":              funcRound,
-	"scalar":             funcScalar,
-	"sgn":                funcSgn,
-	"sin":                funcSin,
-	"sinh":               funcSinh,
-	"sort":               funcSort,
-	"sort_desc":          funcSortDesc,
-	"sort_by_label":      funcSortByLabel,
-	"sort_by_label_desc": funcSortByLabelDesc,
-	"sqrt":               funcSqrt,
-	"stddev_over_time":   funcStddevOverTime,
-	"stdvar_over_time":   funcStdvarOverTime,
-	"sum_over_time":      funcSumOverTime,
-	"tan":                funcTan,
-	"tanh":               funcTanh,
-	"time":               funcTime,
-	"timestamp":          funcTimestamp,
-	"vector":             funcVector,
-	"year":               funcYear,
+	"abs":                          funcAbs,
+	"absent":                       funcAbsent,
+	"absent_over_time":             funcAbsentOverTime,
+	"acos":                         funcAcos,
+	"acosh":                        funcAcosh,
+	"asin":                         funcAsin,
+	"asinh":                        funcAsinh,
+	"atan":                         funcAtan,
+	"atanh":                        funcAtanh,
+	"avg_over_time":                funcAvgOverTime,
+	"ceil":                         funcCeil,
+	"changes":                      funcChanges,
+	"clamp":                        funcClamp,
+	"clamp_max":                    funcClampMax,
+	"clamp_min":                    funcClampMin,
+	"cos":                          funcCos,
+	"cosh":                         funcCosh,
+	"count_over_time":              funcCountOverTime,
+	"days_in_month":                funcDaysInMonth,
+	"day_of_month":                 funcDayOfMonth,
+	"day_of_week":                  funcDayOfWeek,
+	"day_of_year":                  funcDayOfYear,
+	"deg":                          funcDeg,
+	"delta":                        funcDelta,
+	"deriv":                        funcDeriv,
+	"exp":                          funcExp,
+	"floor":                        funcFloor,
+	"histogram_avg":                funcHistogramAvg,
+	"histogram_count":              funcHistogramCount,
+	"histogram_fraction":           funcHistogramFraction,
+	"histogram_quantile":           funcHistogramQuantile,
+	"histogram_sum":                funcHistogramSum,
+	"histogram_stddev":             funcHistogramStdDev,
+	"histogram_stdvar":             funcHistogramStdVar,
+	"double_exponential_smoothing": funcDoubleExponentialSmoothing,
+	"hour":                         funcHour,
+	"idelta":                       funcIdelta,
+	"increase":                     funcIncrease,
+	"irate":                        funcIrate,
+	"label_replace":                funcLabelReplace,
+	"label_join":                   funcLabelJoin,
+	"ln":                           funcLn,
+	"log10":                        funcLog10,
+	"log2":                         funcLog2,
+	"last_over_time":               funcLastOverTime,
+	"mad_over_time":                funcMadOverTime,
+	"max_over_time":                funcMaxOverTime,
+	"min_over_time":                funcMinOverTime,
+	"minute":                       funcMinute,
+	"month":                        funcMonth,
+	"pi":                           funcPi,
+	"predict_linear":               funcPredictLinear,
+	"present_over_time":            funcPresentOverTime,
+	"quantile_over_time":           funcQuantileOverTime,
+	"rad":                          funcRad,
+	"rate":                         funcRate,
+	"resets":                       funcResets,
+	"round":                        funcRound,
+	"scalar":                       funcScalar,
+	"sgn":                          funcSgn,
+	"sin":                          funcSin,
+	"sinh":                         funcSinh,
+	"sort":                         funcSort,
+	"sort_desc":                    funcSortDesc,
+	"sort_by_label":                funcSortByLabel,
+	"sort_by_label_desc":           funcSortByLabelDesc,
+	"sqrt":                         funcSqrt,
+	"stddev_over_time":             funcStddevOverTime,
+	"stdvar_over_time":             funcStdvarOverTime,
+	"sum_over_time":                funcSumOverTime,
+	"tan":                          funcTan,
+	"tanh":                         funcTanh,
+	"time":                         funcTime,
+	"timestamp":                    funcTimestamp,
+	"vector":                       funcVector,
+	"year":                         funcYear,
 }
 
 // AtModifierUnsafeFunctions are the functions whose result
diff --git a/promql/parser/functions.go b/promql/parser/functions.go
@@ -202,8 +202,8 @@ var Functions = map[string]*Function{
 		ArgTypes:   []ValueType{ValueTypeScalar, ValueTypeVector},
 		ReturnType: ValueTypeVector,
 	},
-	"holt_winters": {
-		Name:         "holt_winters",
+	"double_exponential_smoothing": {
+		Name:         "double_exponential_smoothing",
 		ArgTypes:     []ValueType{ValueTypeMatrix, ValueTypeScalar, ValueTypeScalar},
 		ReturnType:   ValueTypeVector,
 		Experimental: true,
diff --git a/promql/promqltest/testdata/functions.test b/promql/promqltest/testdata/functions.test
@@ -651,7 +651,7 @@ eval_ordered instant at 50m sort_by_label(node_uname_info, "release")
 	node_uname_info{job="node_exporter", instance="4m5", release="1.11.3"} 100
 	node_uname_info{job="node_exporter", instance="4m1000", release="1.111.3"} 100
 
-# Tests for holt_winters
+# Tests for double_exponential_smoothing
 clear
 
 # positive trends
@@ -661,7 +661,7 @@ load 10s
 	http_requests{job="api-server", instance="0", group="canary"}		0+30x1000 300+80x1000
 	http_requests{job="api-server", instance="1", group="canary"}		0+40x2000
 
-eval instant at 8000s holt_winters(http_requests[1m], 0.01, 0.1)
+eval instant at 8000s double_exponential_smoothing(http_requests[1m], 0.01, 0.1)
 	{job="api-server", instance="0", group="production"} 8000
 	{job="api-server", instance="1", group="production"} 16000
 	{job="api-server", instance="0", group="canary"} 24000
@@ -675,7 +675,7 @@ load 10s
 	http_requests{job="api-server", instance="0", group="canary"}		0+30x1000 300-80x1000
 	http_requests{job="api-server", instance="1", group="canary"}		0-40x1000 0+40x1000
 
-eval instant at 8000s holt_winters(http_requests[1m], 0.01, 0.1)
+eval instant at 8000s double_exponential_smoothing(http_requests[1m], 0.01, 0.1)
 	{job="api-server", instance="0", group="production"} 0
 	{job="api-server", instance="1", group="production"} -16000
 	{job="api-server", instance="0", group="canary"} 24000
diff --git a/ui-commits b/ui-commits
@@ -0,0 +1,12 @@
+dfec29d8e Fix border color for target pools with one target that is failing
+65743bf9b ui: drop template readme
+a7c1a951d Add general Mantine overrides CSS file
+0757fbbec Make sure that alert element table headers are not wrapped
+0180cf31a Factor out common icon and card styles
+50af7d589 Fix tree line drawing by using a callback ref
+ac01dc903 Explain, vector-to-vector: Do not compute results for set operators
+9b0dc68d0 PromQL explain view: Support set operators
+57898c792 Refactor and fix time formatting functions, add tests
+091fc403c Fiddle with targets table styles to try and improve things a bit
+a1908df92 Don't wrap action buttons below metric name in metrics explorer
+ac5377873 mantine UI: Distinguish between Not Ready and Stopping
diff --git a/web/ui/mantine-ui/src/promql/functionDocs.tsx b/web/ui/mantine-ui/src/promql/functionDocs.tsx
@@ -1277,17 +1277,17 @@ const funcDocs: Record<string, React.ReactNode> = {
       </p>
     </>
   ),
-  holt_winters: (
+  double_exponential_smoothing: (
     <>
       <p>
-        <code>holt_winters(v range-vector, sf scalar, tf scalar)</code> produces a smoothed value for time series based on
+        <code>double_exponential_smoothing(v range-vector, sf scalar, tf scalar)</code> produces a smoothed value for time series based on
         the range in <code>v</code>. The lower the smoothing factor <code>sf</code>, the more importance is given to old
         data. The higher the trend factor <code>tf</code>, the more trends in the data is considered. Both <code>sf</code>{' '}
         and <code>tf</code> must be between 0 and 1.
       </p>
 
       <p>
-        <code>holt_winters</code> should only be used with gauges.
+        <code>double_exponential_smoothing</code> should only be used with gauges.
       </p>
     </>
   ),
diff --git a/web/ui/mantine-ui/src/promql/functionMeta.ts b/web/ui/mantine-ui/src/promql/functionMeta.ts
@@ -17,7 +17,7 @@ export const functionArgNames: Record<string, string[]> = {
   // exp: [],
   // floor: [],
   histogram_quantile: ['target quantile', 'histogram'],
-  holt_winters: ['input series', 'smoothing factor', 'trend factor'],
+  double_exponential_smoothing: ['input series', 'smoothing factor', 'trend factor'],
   hour: ['timestamp (default = vector(time()))'],
   // idelta: [],
   // increase: [],
@@ -68,7 +68,7 @@ export const functionDescriptions: Record<string, string> = {
   exp: 'calculate exponential function for input vector values',
   floor: 'round down values of input series to nearest integer',
   histogram_quantile: 'calculate quantiles from histogram buckets',
-  holt_winters: 'calculate smoothed value of input series',
+  double_exponential_smoothing: 'calculate smoothed value of input series',
   hour: 'return the hour of the day for provided timestamps',
   idelta: 'calculate the difference between the last two samples of a range vector (for counters)',
   increase: 'calculate the increase in value over a range of time (for counters)',
diff --git a/web/ui/mantine-ui/src/promql/functionSignatures.ts b/web/ui/mantine-ui/src/promql/functionSignatures.ts
@@ -60,8 +60,8 @@ export const functionSignatures: Record<string, Func> = {
   histogram_stddev: { name: 'histogram_stddev', argTypes: [valueType.vector], variadic: 0, returnType: valueType.vector },
   histogram_stdvar: { name: 'histogram_stdvar', argTypes: [valueType.vector], variadic: 0, returnType: valueType.vector },
   histogram_sum: { name: 'histogram_sum', argTypes: [valueType.vector], variadic: 0, returnType: valueType.vector },
-  holt_winters: {
-    name: 'holt_winters',
+  double_exponential_smoothing: {
+    name: 'double_exponential_smoothing',
     argTypes: [valueType.matrix, valueType.scalar, valueType.scalar],
     variadic: 0,
     returnType: valueType.vector,
diff --git a/web/ui/module/codemirror-promql/src/complete/promql.terms.ts b/web/ui/module/codemirror-promql/src/complete/promql.terms.ts
@@ -258,7 +258,7 @@ export const functionIdentifierTerms = [
     type: 'function',
   },
   {
-    label: 'holt_winters',
+    label: 'double_exponential_smoothing',
     detail: 'function',
     info: 'Calculate smoothed value of input series',
     type: 'function',
diff --git a/web/ui/module/codemirror-promql/src/types/function.ts b/web/ui/module/codemirror-promql/src/types/function.ts
@@ -46,7 +46,7 @@ import {
   HistogramStdDev,
   HistogramStdVar,
   HistogramSum,
-  HoltWinters,
+  DoubleExponentialSmoothing,
   Hour,
   Idelta,
   Increase,
@@ -312,8 +312,8 @@ const promqlFunctions: { [key: number]: PromQLFunction } = {
     variadic: 0,
     returnType: ValueType.vector,
   },
-  [HoltWinters]: {
-    name: 'holt_winters',
+  [DoubleExponentialSmoothing]: {
+    name: 'double_exponential_smoothing',
     argTypes: [ValueType.matrix, ValueType.scalar, ValueType.scalar],
     variadic: 0,
     returnType: ValueType.vector,
diff --git a/web/ui/module/lezer-promql/src/highlight.js b/web/ui/module/lezer-promql/src/highlight.js
@@ -20,7 +20,7 @@ export const promQLHighLight = styleTags({
     NumberDurationLiteral: tags.number,
     NumberDurationLiteralInDurationContext: tags.number,
     Identifier: tags.variableName,
-    'Abs Absent AbsentOverTime Acos Acosh Asin Asinh Atan Atanh AvgOverTime Ceil Changes Clamp ClampMax ClampMin Cos Cosh CountOverTime DaysInMonth DayOfMonth DayOfWeek DayOfYear Deg Delta Deriv Exp Floor HistogramAvg HistogramCount HistogramFraction HistogramQuantile HistogramSum HoltWinters Hour Idelta Increase Irate LabelReplace LabelJoin LastOverTime Ln Log10 Log2 MaxOverTime MinOverTime Minute Month Pi PredictLinear PresentOverTime QuantileOverTime Rad Rate Resets Round Scalar Sgn Sin Sinh Sort SortDesc SortByLabel SortByLabelDesc Sqrt StddevOverTime StdvarOverTime SumOverTime Tan Tanh Time Timestamp Vector Year':
+    'Abs Absent AbsentOverTime Acos Acosh Asin Asinh Atan Atanh AvgOverTime Ceil Changes Clamp ClampMax ClampMin Cos Cosh CountOverTime DaysInMonth DayOfMonth DayOfWeek DayOfYear Deg Delta Deriv Exp Floor HistogramAvg HistogramCount HistogramFraction HistogramQuantile HistogramSum DoubleExponentialSmoothing Hour Idelta Increase Irate LabelReplace LabelJoin LastOverTime Ln Log10 Log2 MaxOverTime MinOverTime Minute Month Pi PredictLinear PresentOverTime QuantileOverTime Rad Rate Resets Round Scalar Sgn Sin Sinh Sort SortDesc SortByLabel SortByLabelDesc Sqrt StddevOverTime StdvarOverTime SumOverTime Tan Tanh Time Timestamp Vector Year':
         tags.function(tags.variableName),
     'Avg Bottomk Count Count_values Group LimitK LimitRatio Max Min Quantile Stddev Stdvar Sum Topk': tags.operatorKeyword,
     'By Without Bool On Ignoring GroupLeft GroupRight Offset Start End': tags.modifier,
diff --git a/web/ui/module/lezer-promql/src/promql.grammar b/web/ui/module/lezer-promql/src/promql.grammar
@@ -141,7 +141,7 @@ FunctionIdentifier {
   HistogramStdVar |
   HistogramSum |
   HistogramAvg |
-  HoltWinters |
+  DoubleExponentialSmoothing |
   Hour |
   Idelta |
   Increase |
@@ -388,7 +388,7 @@ NumberDurationLiteralInDurationContext {
   HistogramStdDev { condFn<"histogram_stddev"> }
   HistogramStdVar { condFn<"histogram_stdvar"> }
   HistogramSum { condFn<"histogram_sum"> }
-  HoltWinters { condFn<"holt_winters"> }
+  DoubleExponentialSmoothing { condFn<"double_exponential_smoothing"> }
   Hour { condFn<"hour"> }
   Idelta { condFn<"idelta"> }
   Increase { condFn<"increase"> }

Original file line number	Diff line number	Diff line change
`@@ -117,7 +117,7 @@ func rangeQueryCases() []benchCase {`
`117`	`117`	`},`
`118`	`118`	`// Holt-Winters and long ranges.`
`119`	`119`	`{`
`120`		`- expr: "holt_winters(a_X[1d], 0.3, 0.3)",`
	`120`	`+ expr: "double_exponential_smoothing(a_X[1d], 0.3, 0.3)",`
`121`	`121`	`},`
`122`	`122`	`{`
`123`	`123`	`expr: "changes(a_X[1d])",`
Original file line number	Diff line number	Diff line change
`@@ -258,7 +258,7 @@ export const functionIdentifierTerms = [`
`258`	`258`	`type: 'function',`
`259`	`259`	`},`
`260`	`260`	`{`
`261`		`- label: 'holt_winters',`
	`261`	`+ label: 'double_exponential_smoothing',`
`262`	`262`	`detail: 'function',`
`263`	`263`	`info: 'Calculate smoothed value of input series',`
`264`	`264`	`type: 'function',`