Merge pull request #14232 from vespa-engine/bratseth/decode-once

Decode once

2 files changed, 28 insertions, 0 deletions

diff --git a/container-search/src/main/java/com/yahoo/search/result/FeatureData.java b/container-search/src/main/java/com/yahoo/search/result/FeatureData.java
index 4895db04462..f0637473ef5 100644
--- a/container-search/src/main/java/com/yahoo/search/result/FeatureData.java
+++ b/container-search/src/main/java/com/yahoo/search/result/FeatureData.java
@@ -14,7 +14,9 @@ import com.yahoo.tensor.serialization.TypedBinaryFormat;
 
 import java.nio.charset.StandardCharsets;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 
@@ -31,6 +33,10 @@ public class FeatureData implements Inspectable, JsonProducer {
 
     private Set<String> featureNames = null;
 
+    /** Cached decoded values */
+    private Map<String, Double> decodedDoubles = null;
+    private Map<String, Tensor> decodedTensors = null;
+
     private String jsonForm = null;
 
     public FeatureData(Inspector value) {
@@ -68,6 +74,16 @@ public class FeatureData implements Inspectable, JsonProducer {
      *                                  (that is, if it is a tensor with nonzero rank)
      */
     public Double getDouble(String featureName) {
+        if (decodedDoubles != null && decodedDoubles.containsKey(featureName))
+            return decodedDoubles.get(featureName);
+        Double value = decodeDouble(featureName);
+        if (decodedDoubles == null)
+            decodedDoubles = new HashMap<>();
+        decodedDoubles.put(featureName, value);
+        return value;
+    }
+
+    private Double decodeDouble(String featureName) {
         Inspector featureValue = getInspector(featureName);
         if ( ! featureValue.valid()) return null;
 
@@ -83,6 +99,16 @@ public class FeatureData implements Inspectable, JsonProducer {
      * This will return any feature value: Scalars are returned as a rank 0 tensor.
      */
     public Tensor getTensor(String featureName) {
+        if (decodedTensors != null && decodedTensors.containsKey(featureName))
+            return decodedTensors.get(featureName);
+        Tensor value = decodeTensor(featureName);
+        if (decodedTensors == null)
+            decodedTensors = new HashMap<>();
+        decodedTensors.put(featureName, value);
+        return value;
+    }
+
+    private Tensor decodeTensor(String featureName) {
         Inspector featureValue = getInspector(featureName);
         if ( ! featureValue.valid()) return null;
 
diff --git a/container-search/src/test/java/com/yahoo/search/result/FeatureDataTestCase.java b/container-search/src/test/java/com/yahoo/search/result/FeatureDataTestCase.java
index 9cc7cc743fc..f9b89b64e5b 100644
--- a/container-search/src/test/java/com/yahoo/search/result/FeatureDataTestCase.java
+++ b/container-search/src/test/java/com/yahoo/search/result/FeatureDataTestCase.java
@@ -34,10 +34,12 @@ public class FeatureDataTestCase {
                      featureData.featureNames().stream().sorted().collect(Collectors.joining(",")));
         assertEquals(1.5, featureData.getDouble("scalar1"), delta);
         assertEquals(2.5, featureData.getDouble("scalar2"), delta);
+        assertEquals("Cached lookup", 2.5, featureData.getDouble("scalar2"), delta);
         assertEquals(Tensor.from(1.5), featureData.getTensor("scalar1"));
         assertEquals(Tensor.from(2.5), featureData.getTensor("scalar2"));
         assertEquals(tensor1, featureData.getTensor("tensor1"));
         assertEquals(tensor2, featureData.getTensor("tensor2"));
+        assertEquals("Cached lookup", tensor2, featureData.getTensor("tensor2"));
 
         String expectedJson =
                 "{" +