perf(nhcbparse): unroll recursion (#15776)

https://github.com/prometheus/prometheus/pull/15467#issuecomment-2563585979 Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
2025-03-05 20:59:13 -08:00 · 2025-01-02 15:51:52 +01:00 · 2025-01-02 15:51:52 +01:00 · cfcb00a716
parent 1e420ef373
commit cfcb00a716
1 changed files with 48 additions and 46 deletions
--- a/model/textparse/nhcbparse.go
+++ b/model/textparse/nhcbparse.go
@ -177,13 +177,14 @@ func (p *NHCBParser) CreatedTimestamp() *int64 {
 }

 func (p *NHCBParser) Next() (Entry, error) {
+	for {
 		if p.state == stateEmitting {
 			p.state = stateStart
 			if p.entry == EntrySeries {
 				isNHCB := p.handleClassicHistogramSeries(p.lset)
 				if isNHCB && !p.keepClassicHistograms {
 					// Do not return the classic histogram series if it was converted to NHCB and we are not keeping classic histograms.
-				return p.Next()
+					continue
 				}
 			}
 			return p.entry, p.err
@ -218,7 +219,7 @@ func (p *NHCBParser) Next() (Entry, error) {
 			}
 			if isNHCB && !p.keepClassicHistograms {
 				// Do not return the classic histogram series if it was converted to NHCB and we are not keeping classic histograms.
-			return p.Next()
+				continue
 			}
 			return p.entry, p.err
 		case EntryHistogram:
@ -232,6 +233,7 @@ func (p *NHCBParser) Next() (Entry, error) {
 			return EntryHistogram, nil
 		}
 		return p.entry, p.err
+	}
 }

 // Return true if labels have changed and we should emit the NHCB.