tsdb/wlog: Only treat unknown record types as failure

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

CHANGELOG.md

@@ -7,6 +7,7 @@
 * [ENHANCEMENT] OTLP: Improve remote write format translation performance by using label set hashes for metric identifiers instead of string based ones. #14006 #13991
 * [BUGFIX] OTLP: Don't generate target_info unless at least one identifying label is defined. #13991
 * [BUGFIX] OTLP: Don't generate target_info unless there are metrics. #13991
+* [BUGFIX] tsdb/wlog.Watcher.readSegmentForGC: Only count unknown record types against record_decode_failures_total metric. #14042
 
 ## 2.52.0-rc.1 / 2024-05-03
 

tsdb/wlog/watcher.go

@@ -685,14 +685,12 @@ func (w *Watcher) readSegmentForGC(r *LiveReader, segmentNum int, _ bool) error
 			}
 			w.writer.UpdateSeriesSegment(series, segmentNum)
 
-		// Ignore these; we're only interested in series.
-		case record.Samples:
-		case record.Exemplars:
-		case record.Tombstones:
-
-		default:
+		case record.Unknown:
 			// Could be corruption, or reading from a WAL from a newer Prometheus.
 			w.recordDecodeFailsMetric.Inc()
+
+		default:
+			// We're only interested in series.
 		}
 	}
 	if err := r.Err(); err != nil {