promql: faster range-query of label_replace and label_join

These functions act on the labels only, so don't need to go step by step
over the samples in a range query.

Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
This commit is contained in:
Bryan Boreham 2024-02-04 11:08:20 +01:00
parent 805d51f6d3
commit fdd5b85e06
2 changed files with 57 additions and 81 deletions

View file

@ -1409,6 +1409,15 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
break
}
}
// Special handling for functions that work on series not samples.
switch e.Func.Name {
case "label_replace":
return ev.evalLabelReplace(e.Args)
case "label_join":
return ev.evalLabelJoin(e.Args)
}
if !matrixArg {
// Does not have a matrix argument.
return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {

View file

@ -1321,59 +1321,47 @@ func funcChanges(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelp
return append(enh.Out, Sample{F: float64(changes)}), nil
}
// === label_replace(Vector parser.ValueTypeVector, dst_label, replacement, src_labelname, regex parser.ValueTypeString) (Vector, Annotations) ===
func funcLabelReplace(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
// label_replace function operates only on series; does not look at timestamps or values.
func (ev *evaluator) evalLabelReplace(args parser.Expressions) (parser.Value, annotations.Annotations) {
var (
vector = vals[0].(Vector)
dst = stringFromArg(args[1])
repl = stringFromArg(args[2])
src = stringFromArg(args[3])
regexStr = stringFromArg(args[4])
)
if enh.regex == nil {
var err error
enh.regex, err = regexp.Compile("^(?:" + regexStr + ")$")
if err != nil {
panic(fmt.Errorf("invalid regular expression in label_replace(): %s", regexStr))
}
if !model.LabelNameRE.MatchString(dst) {
panic(fmt.Errorf("invalid destination label name in label_replace(): %s", dst))
}
enh.Dmn = make(map[uint64]labels.Labels, len(enh.Out))
regex, err := regexp.Compile("^(?:" + regexStr + ")$")
if err != nil {
panic(fmt.Errorf("invalid regular expression in label_replace(): %s", regexStr))
}
if !model.LabelNameRE.MatchString(dst) {
panic(fmt.Errorf("invalid destination label name in label_replace(): %s", dst))
}
for _, el := range vector {
h := el.Metric.Hash()
var outMetric labels.Labels
if l, ok := enh.Dmn[h]; ok {
outMetric = l
} else {
srcVal := el.Metric.Get(src)
indexes := enh.regex.FindStringSubmatchIndex(srcVal)
if indexes == nil {
// If there is no match, no replacement should take place.
outMetric = el.Metric
enh.Dmn[h] = outMetric
} else {
res := enh.regex.ExpandString([]byte{}, repl, srcVal, indexes)
val, ws := ev.eval(args[0])
matrix := val.(Matrix)
lb := labels.NewBuilder(labels.EmptyLabels())
lb := labels.NewBuilder(el.Metric).Del(dst)
if len(res) > 0 {
lb.Set(dst, string(res))
}
outMetric = lb.Labels()
enh.Dmn[h] = outMetric
}
for i, el := range matrix {
srcVal := el.Metric.Get(src)
indexes := regex.FindStringSubmatchIndex(srcVal)
if indexes != nil { // Only replace when regexp matches.
res := regex.ExpandString([]byte{}, repl, srcVal, indexes)
lb.Reset(el.Metric)
lb.Set(dst, string(res))
matrix[i].Metric = lb.Labels()
}
enh.Out = append(enh.Out, Sample{
Metric: outMetric,
F: el.F,
H: el.H,
})
}
return enh.Out, nil
if matrix.ContainsSameLabelset() {
ev.errorf("vector cannot contain metrics with the same labelset")
}
return matrix, ws
}
// === label_replace(Vector parser.ValueTypeVector, dst_label, replacement, src_labelname, regex parser.ValueTypeString) (Vector, Annotations) ===
func funcLabelReplace(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
panic("funcLabelReplace wrong implementation called")
}
// === Vector(s Scalar) (Vector, Annotations) ===
@ -1385,19 +1373,13 @@ func funcVector(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelpe
}), nil
}
// === label_join(vector model.ValVector, dest_labelname, separator, src_labelname...) (Vector, Annotations) ===
func funcLabelJoin(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
// label_join function operates only on series; does not look at timestamps or values.
func (ev *evaluator) evalLabelJoin(args parser.Expressions) (parser.Value, annotations.Annotations) {
var (
vector = vals[0].(Vector)
dst = stringFromArg(args[1])
sep = stringFromArg(args[2])
srcLabels = make([]string, len(args)-3)
)
if enh.Dmn == nil {
enh.Dmn = make(map[uint64]labels.Labels, len(enh.Out))
}
for i := 3; i < len(args); i++ {
src := stringFromArg(args[i])
if !model.LabelName(src).IsValid() {
@ -1406,42 +1388,27 @@ func funcLabelJoin(vals []parser.Value, args parser.Expressions, enh *EvalNodeHe
srcLabels[i-3] = src
}
if !model.LabelName(dst).IsValid() {
panic(fmt.Errorf("invalid destination label name in label_join(): %s", dst))
}
val, ws := ev.eval(args[0])
matrix := val.(Matrix)
srcVals := make([]string, len(srcLabels))
for _, el := range vector {
h := el.Metric.Hash()
var outMetric labels.Labels
if l, ok := enh.Dmn[h]; ok {
outMetric = l
} else {
lb := labels.NewBuilder(labels.EmptyLabels())
for i, src := range srcLabels {
srcVals[i] = el.Metric.Get(src)
}
lb := labels.NewBuilder(el.Metric)
strval := strings.Join(srcVals, sep)
if strval == "" {
lb.Del(dst)
} else {
lb.Set(dst, strval)
}
outMetric = lb.Labels()
enh.Dmn[h] = outMetric
for i, el := range matrix {
for i, src := range srcLabels {
srcVals[i] = el.Metric.Get(src)
}
enh.Out = append(enh.Out, Sample{
Metric: outMetric,
F: el.F,
H: el.H,
})
strval := strings.Join(srcVals, sep)
lb.Reset(el.Metric)
lb.Set(dst, strval)
matrix[i].Metric = lb.Labels()
}
return enh.Out, nil
return matrix, ws
}
// === label_join(vector model.ValVector, dest_labelname, separator, src_labelname...) (Vector, Annotations) ===
func funcLabelJoin(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
panic("funcLabelReplace wrong implementation called")
}
// Common code for date related functions.