[FLINK-12981][metrics] ignore NaNs in percentile implementation

Histrogram metrics use "long" values anyway and therefore, there is no NaN in the DescriptiveStatistics' data.
deepfield · Aug 21, 2019 · e59b9d2 · e59b9d2
1 parent 76460d9
commit e59b9d2
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/...untime/src/main/java/org/apache/flink/runtime/metrics/DescriptiveStatisticsHistogram.java b/...untime/src/main/java/org/apache/flink/runtime/metrics/DescriptiveStatisticsHistogram.java
@@ -21,6 +21,8 @@
 import org.apache.flink.metrics.HistogramStatistics;
 
 import org.apache.commons.math3.stat.descriptive.DescriptiveStatistics;
+import org.apache.commons.math3.stat.descriptive.rank.Percentile;
+import org.apache.commons.math3.stat.ranking.NaNStrategy;
 
 /**
  * The {@link DescriptiveStatisticsHistogram} use a DescriptiveStatistics {@link DescriptiveStatistics} as a Flink {@link Histogram}.
@@ -33,6 +35,9 @@ public class DescriptiveStatisticsHistogram implements org.apache.flink.metrics.
 
  public DescriptiveStatisticsHistogram(int windowSize) {
  this.descriptiveStatistics = new DescriptiveStatistics(windowSize);
+ // since we are storing Long values, we won't have NaN values
+ Percentile percentileImpl = new Percentile().withNaNStrategy(NaNStrategy.FIXED);
+ descriptiveStatistics.setPercentileImpl(percentileImpl);
  }
 
  @Override