VictoriaMetrics/lib/logstorage/stats_max.go

102 lines
2.1 KiB
Go

package logstorage
import (
"math"
"slices"
"strconv"
"unsafe"
)
type statsMax struct {
fields []string
containsStar bool
}
func (sm *statsMax) String() string {
return "max(" + fieldNamesString(sm.fields) + ")"
}
func (sm *statsMax) neededFields() []string {
return sm.fields
}
func (sm *statsMax) newStatsProcessor() (statsProcessor, int) {
smp := &statsMaxProcessor{
sm: sm,
max: nan,
}
return smp, int(unsafe.Sizeof(*smp))
}
type statsMaxProcessor struct {
sm *statsMax
max float64
}
func (smp *statsMaxProcessor) updateStatsForAllRows(br *blockResult) int {
if smp.sm.containsStar {
// Find the maximum value across all the columns
for _, c := range br.getColumns() {
f := c.getMaxValue()
if f > smp.max || math.IsNaN(smp.max) {
smp.max = f
}
}
} else {
// Find the maximum value across the requested columns
for _, field := range smp.sm.fields {
c := br.getColumnByName(field)
f := c.getMaxValue()
if f > smp.max || math.IsNaN(smp.max) {
smp.max = f
}
}
}
return 0
}
func (smp *statsMaxProcessor) updateStatsForRow(br *blockResult, rowIdx int) int {
if smp.sm.containsStar {
// Find the maximum value across all the fields for the given row
for _, c := range br.getColumns() {
f := c.getFloatValueAtRow(rowIdx)
if f > smp.max || math.IsNaN(smp.max) {
smp.max = f
}
}
} else {
// Find the maximum value across the requested fields for the given row
for _, field := range smp.sm.fields {
c := br.getColumnByName(field)
f := c.getFloatValueAtRow(rowIdx)
if f > smp.max || math.IsNaN(smp.max) {
smp.max = f
}
}
}
return 0
}
func (smp *statsMaxProcessor) mergeState(sfp statsProcessor) {
src := sfp.(*statsMaxProcessor)
if src.max > smp.max {
smp.max = src.max
}
}
func (smp *statsMaxProcessor) finalizeStats() string {
return strconv.FormatFloat(smp.max, 'g', -1, 64)
}
func parseStatsMax(lex *lexer) (*statsMax, error) {
fields, err := parseFieldNamesForStatsFunc(lex, "max")
if err != nil {
return nil, err
}
sm := &statsMax{
fields: fields,
containsStar: slices.Contains(fields, "*"),
}
return sm, nil
}