diff --git a/lib/oplog/tail.go b/lib/oplog/tail.go
index ca8f26a5..23ffd497 100644
--- a/lib/oplog/tail.go
+++ b/lib/oplog/tail.go
@@ -354,7 +354,7 @@ func (tailer *Tailer) unmarshalEntry(rawData bson.Raw) (timestamp *primitive.Tim
 
 		metricOplogEntriesBySize.WithLabelValues(database, status).Observe(messageLen)
 		metricMaxOplogEntryByMinute.Report(messageLen, database, status)
-		metricLastOplogEntryStaleness.Set(float64(uint32(time.Now().Unix()) - timestamp.T))
+		metricLastOplogEntryStaleness.Set(float64(time.Since(time.Unix(int64(timestamp.T), 0))))
 	}()
 
 	if len(entries) > 0 {
diff --git a/lib/redispub/publisher.go b/lib/redispub/publisher.go
index 69f83374..c5b4397f 100644
--- a/lib/redispub/publisher.go
+++ b/lib/redispub/publisher.go
@@ -168,7 +168,7 @@ func publishSingleMessage(p *Publication, client redis.UniversalClient, prefix s
 		strings.Join(p.Channels, "$"), // ARGV[3], channels
 	).Result()
 
-	metricLastCommandDuration.Set(time.Now().Sub(start).Seconds())
+	metricLastCommandDuration.Set(time.Since(start).Seconds())
 	return err
 }