make HNSW distance metric configurable

26 files changed, 167 insertions, 13 deletions

diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/derived/AttributeFields.java b/config-model/src/main/java/com/yahoo/searchdefinition/derived/AttributeFields.java
index 8de8b239c93..5b87fdcf5f6 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/derived/AttributeFields.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/derived/AttributeFields.java
@@ -246,6 +246,8 @@ public class AttributeFields extends Derived implements AttributesConfig.Produce
             ib.hnsw.enabled(true);
             ib.hnsw.maxlinkspernode(params.maxLinksPerNode());
             ib.hnsw.neighborstoexploreatinsert(params.neighborsToExploreAtInsert());
+            var dm = AttributesConfig.Attribute.Index.Hnsw.Distancemetric.Enum.valueOf(params.distanceMetric().toString());
+            ib.hnsw.distancemetric(dm);
             aaB.index(ib);
         }
         return aaB;
diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/document/HnswIndexParams.java b/config-model/src/main/java/com/yahoo/searchdefinition/document/HnswIndexParams.java
index 70d0df8be7f..01434be8785 100644
--- a/config-model/src/main/java/com/yahoo/searchdefinition/document/HnswIndexParams.java
+++ b/config-model/src/main/java/com/yahoo/searchdefinition/document/HnswIndexParams.java
@@ -1,7 +1,8 @@
 // Copyright 2020 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.searchdefinition.document;
 
-import java.util.OptionalInt;
+import java.util.Locale;
+import java.util.Optional;
 
 /**
  * Configuration parameters for a hnsw index used together with a 1-dimensional indexed tensor for approximate nearest neighbor search.
@@ -12,33 +13,47 @@ public class HnswIndexParams {
 
     public static final int DEFAULT_MAX_LINKS_PER_NODE = 16;
     public static final int DEFAULT_NEIGHBORS_TO_EXPLORE_AT_INSERT = 200;
+    public static final DistanceMetric DEFAULT_DISTANCE_METRIC = DistanceMetric.EUCLIDEAN;
 
-    private final OptionalInt maxLinksPerNode;
-    private final OptionalInt neighborsToExploreAtInsert;
+    private final Optional<Integer> maxLinksPerNode;
+    private final Optional<Integer> neighborsToExploreAtInsert;
+    private final Optional<DistanceMetric> distanceMetric;
+
+    public static enum DistanceMetric { EUCLIDEAN, ANGULAR, GEODEGREES }
 
     public static class Builder {
-        private OptionalInt maxLinksPerNode = OptionalInt.empty();
-        private OptionalInt neighborsToExploreAtInsert = OptionalInt.empty();
+        private Optional<Integer> maxLinksPerNode = Optional.empty();
+        private Optional<Integer> neighborsToExploreAtInsert = Optional.empty();
+        private Optional<DistanceMetric> distanceMetric = Optional.empty();
 
         public void setMaxLinksPerNode(int value) {
-            maxLinksPerNode = OptionalInt.of(value);
+            maxLinksPerNode = Optional.of(value);
         }
         public void setNeighborsToExploreAtInsert(int value) {
-            neighborsToExploreAtInsert = OptionalInt.of(value);
+            neighborsToExploreAtInsert = Optional.of(value);
+        }
+        public void setDistanceMetric(String value) {
+            String upper = value.toUpperCase(Locale.ENGLISH);
+            DistanceMetric dm = DistanceMetric.valueOf(upper);
+            distanceMetric = Optional.of(dm);
         }
         public HnswIndexParams build() {
-            return new HnswIndexParams(maxLinksPerNode, neighborsToExploreAtInsert);
+            return new HnswIndexParams(maxLinksPerNode, neighborsToExploreAtInsert, distanceMetric);
         }
     }
 
     public HnswIndexParams() {
-        this.maxLinksPerNode = OptionalInt.empty();
-        this.neighborsToExploreAtInsert = OptionalInt.empty();
+        this.maxLinksPerNode = Optional.empty();
+        this.neighborsToExploreAtInsert = Optional.empty();
+        this.distanceMetric = Optional.empty();
     }
 
-    public HnswIndexParams(OptionalInt maxLinksPerNode, OptionalInt neighborsToExploreAtInsert) {
+    public HnswIndexParams(Optional<Integer> maxLinksPerNode,
+                           Optional<Integer> neighborsToExploreAtInsert,
+                           Optional<DistanceMetric> distanceMetric) {
         this.maxLinksPerNode = maxLinksPerNode;
         this.neighborsToExploreAtInsert = neighborsToExploreAtInsert;
+        this.distanceMetric = distanceMetric;
     }
 
     /**
@@ -46,8 +61,9 @@ public class HnswIndexParams {
      * otherwise we use values from this.
      */
     public HnswIndexParams overrideFrom(HnswIndexParams rhs) {
-        return new HnswIndexParams(rhs.maxLinksPerNode.isPresent() ? rhs.maxLinksPerNode : maxLinksPerNode,
-                rhs.neighborsToExploreAtInsert.isPresent() ? rhs.neighborsToExploreAtInsert : neighborsToExploreAtInsert);
+        return new HnswIndexParams(rhs.maxLinksPerNode.or(() ->  maxLinksPerNode),
+                rhs.neighborsToExploreAtInsert.or(() ->  neighborsToExploreAtInsert),
+                rhs.distanceMetric.or(() -> distanceMetric));
     }
 
     public int maxLinksPerNode() {
@@ -57,4 +73,8 @@ public class HnswIndexParams {
     public int neighborsToExploreAtInsert() {
         return neighborsToExploreAtInsert.orElse(DEFAULT_NEIGHBORS_TO_EXPLORE_AT_INSERT);
     }
+
+    public DistanceMetric distanceMetric() {
+        return distanceMetric.orElse(DEFAULT_DISTANCE_METRIC);
+    }
 }
diff --git a/config-model/src/main/javacc/SDParser.jj b/config-model/src/main/javacc/SDParser.jj
index 2ee0d870d0e..cca56c209c8 100644
--- a/config-model/src/main/javacc/SDParser.jj
+++ b/config-model/src/main/javacc/SDParser.jj
@@ -335,6 +335,7 @@ TOKEN :
 | < ENABLE_BM25: "enable-bm25" >
 | < HNSW: "hnsw" >
 | < MAXLINKSPERNODE: "max-links-per-node" >
+| < DISTANCEMETRIC: "distance-metric" >
 | < NEIGHBORSTOEXPLOREATINSERT: "neighbors-to-explore-at-insert" >
 | < SUMMARYFEATURES_SL: "summary-features" (" ")* ":" (~["}","\n"])* ("\n")? >
 | < SUMMARYFEATURES_ML: "summary-features" (<SEARCHLIB_SKIP>)? "{" (~["}"])* "}" >
@@ -1836,9 +1837,11 @@ void hnswIndex(IndexOperation index) :
 void hnswIndexBody(HnswIndexParams.Builder params) :
 {
     int num;
+    String str;
 }
 {
     ( <MAXLINKSPERNODE> <COLON> num = integer() { params.setMaxLinksPerNode(num); }
+      | <DISTANCEMETRIC> <COLON> str = identifierWithDash()  { params.setDistanceMetric(str); }
       | <NEIGHBORSTOEXPLOREATINSERT> <COLON> num = integer() { params.setNeighborsToExploreAtInsert(num); } )
 }
 
diff --git a/config-model/src/test/derived/advanced/attributes.cfg b/config-model/src/test/derived/advanced/attributes.cfg
index cf8644ebe83..0a76e44c4ac 100644
--- a/config-model/src/test/derived/advanced/attributes.cfg
+++ b/config-model/src/test/derived/advanced/attributes.cfg
@@ -21,4 +21,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/array_of_struct_attribute/attributes.cfg b/config-model/src/test/derived/array_of_struct_attribute/attributes.cfg
index 29d5dd92043..006400c09d4 100644
--- a/config-model/src/test/derived/array_of_struct_attribute/attributes.cfg
+++ b/config-model/src/test/derived/array_of_struct_attribute/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "elem_array.weight"
 attribute[].datatype INT32
@@ -45,4 +46,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/attributeprefetch/attributes.cfg b/config-model/src/test/derived/attributeprefetch/attributes.cfg
index 773f796ed59..cd91c15700b 100644
--- a/config-model/src/test/derived/attributeprefetch/attributes.cfg
+++ b/config-model/src/test/derived/attributeprefetch/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multibyte"
 attribute[].datatype INT8
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wsbyte"
 attribute[].datatype INT8
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "singleint"
 attribute[].datatype INT32
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multiint"
 attribute[].datatype INT32
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wsint"
 attribute[].datatype INT32
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "singlelong"
 attribute[].datatype INT64
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multilong"
 attribute[].datatype INT64
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wslong"
 attribute[].datatype INT64
@@ -213,6 +221,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "singlefloat"
 attribute[].datatype FLOAT
@@ -237,6 +246,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multifloat"
 attribute[].datatype FLOAT
@@ -261,6 +271,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wsfloat"
 attribute[].datatype FLOAT
@@ -285,6 +296,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "singledouble"
 attribute[].datatype DOUBLE
@@ -309,6 +321,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multidouble"
 attribute[].datatype DOUBLE
@@ -333,6 +346,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wsdouble"
 attribute[].datatype DOUBLE
@@ -357,6 +371,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "singlestring"
 attribute[].datatype STRING
@@ -381,6 +396,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "multistring"
 attribute[].datatype STRING
@@ -405,6 +421,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "wsstring"
 attribute[].datatype STRING
@@ -429,4 +446,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/attributes/attributes.cfg b/config-model/src/test/derived/attributes/attributes.cfg
index e3faf7662f4..29e4c209ef2 100644
--- a/config-model/src/test/derived/attributes/attributes.cfg
+++ b/config-model/src/test/derived/attributes/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a2"
 attribute[].datatype STRING
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a3"
 attribute[].datatype STRING
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a5"
 attribute[].datatype STRING
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a6"
 attribute[].datatype STRING
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b1"
 attribute[].datatype STRING
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b2"
 attribute[].datatype STRING
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b3"
 attribute[].datatype STRING
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b4"
 attribute[].datatype INT32
@@ -213,6 +221,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b5"
 attribute[].datatype INT32
@@ -237,6 +246,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b6"
 attribute[].datatype INT64
@@ -261,6 +271,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b7"
 attribute[].datatype DOUBLE
@@ -285,6 +296,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a9"
 attribute[].datatype INT32
@@ -309,6 +321,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a10"
 attribute[].datatype INT32
@@ -333,6 +346,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a11"
 attribute[].datatype INT32
@@ -357,6 +371,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a12"
 attribute[].datatype INT32
@@ -381,6 +396,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a7_arr"
 attribute[].datatype STRING
@@ -405,6 +421,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "a8_arr"
 attribute[].datatype STRING
@@ -429,4 +446,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/complex/attributes.cfg b/config-model/src/test/derived/complex/attributes.cfg
index b4971487bd1..5606e5ea730 100644
--- a/config-model/src/test/derived/complex/attributes.cfg
+++ b/config-model/src/test/derived/complex/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "fleeting"
 attribute[].datatype FLOAT
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "fleeting2"
 attribute[].datatype FLOAT
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "foundat"
 attribute[].datatype INT64
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "collapseby"
 attribute[].datatype INT32
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "ts"
 attribute[].datatype INT64
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "combineda"
 attribute[].datatype INT32
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "year_arr"
 attribute[].datatype INT32
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "year_sub"
 attribute[].datatype INT32
@@ -213,4 +221,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/hnsw_index/attributes.cfg b/config-model/src/test/derived/hnsw_index/attributes.cfg
index 27c9f1e0d13..b61fd7e2ee5 100644
--- a/config-model/src/test/derived/hnsw_index/attributes.cfg
+++ b/config-model/src/test/derived/hnsw_index/attributes.cfg
@@ -21,4 +21,5 @@ attribute[].tensortype "tensor(x[128])"
 attribute[].imported false
 attribute[].index.hnsw.enabled true
 attribute[].index.hnsw.maxlinkspernode 32
+attribute[].index.hnsw.distancemetric ANGULAR
 attribute[].index.hnsw.neighborstoexploreatinsert 300
diff --git a/config-model/src/test/derived/hnsw_index/test.sd b/config-model/src/test/derived/hnsw_index/test.sd
index 03ede04208b..3b954e74fc5 100644
--- a/config-model/src/test/derived/hnsw_index/test.sd
+++ b/config-model/src/test/derived/hnsw_index/test.sd
@@ -5,6 +5,7 @@ search test {
       index {
         hnsw {
           max-links-per-node: 32
+          distance-metric: angular
           neighbors-to-explore-at-insert: 300
         }
       }
diff --git a/config-model/src/test/derived/imported_position_field/attributes.cfg b/config-model/src/test/derived/imported_position_field/attributes.cfg
index 5427e856df0..8f68068c8e7 100644
--- a/config-model/src/test/derived/imported_position_field/attributes.cfg
+++ b/config-model/src/test/derived/imported_position_field/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_pos_zcurve"
 attribute[].datatype INT64
@@ -45,4 +46,5 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/imported_struct_fields/attributes.cfg b/config-model/src/test/derived/imported_struct_fields/attributes.cfg
index e1969e991dd..eb87c6cf53e 100644
--- a/config-model/src/test/derived/imported_struct_fields/attributes.cfg
+++ b/config-model/src/test/derived/imported_struct_fields/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_elem_array.name"
 attribute[].datatype STRING
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_elem_array.weight"
 attribute[].datatype INT32
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_elem_map.key"
 attribute[].datatype STRING
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_elem_map.value.name"
 attribute[].datatype STRING
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_elem_map.value.weight"
 attribute[].datatype INT32
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_str_int_map.key"
 attribute[].datatype STRING
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_str_int_map.value"
 attribute[].datatype INT32
@@ -189,4 +196,5 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/importedfields/attributes.cfg b/config-model/src/test/derived/importedfields/attributes.cfg
index 168c9bd4659..d3a51523e05 100644
--- a/config-model/src/test/derived/importedfields/attributes.cfg
+++ b/config-model/src/test/derived/importedfields/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b_ref"
 attribute[].datatype REFERENCE
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "b_ref_with_summary"
 attribute[].datatype REFERENCE
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_int_field"
 attribute[].datatype INT32
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_string_field"
 attribute[].datatype STRING
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_int_array_field"
 attribute[].datatype INT32
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_int_wset_field"
 attribute[].datatype INT32
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "my_ancient_int_field"
 attribute[].datatype INT32
@@ -189,4 +196,5 @@ attribute[].tensortype ""
 attribute[].imported true
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/inheritance/attributes.cfg b/config-model/src/test/derived/inheritance/attributes.cfg
index 05a980a8347..397d8878792 100644
--- a/config-model/src/test/derived/inheritance/attributes.cfg
+++ b/config-model/src/test/derived/inheritance/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "overridden"
 attribute[].datatype INT32
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "onlymother"
 attribute[].datatype STRING
@@ -69,4 +71,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/inheritfromparent/attributes.cfg b/config-model/src/test/derived/inheritfromparent/attributes.cfg
index 9f01b6c45ce..3b30af10a8f 100644
--- a/config-model/src/test/derived/inheritfromparent/attributes.cfg
+++ b/config-model/src/test/derived/inheritfromparent/attributes.cfg
@@ -21,4 +21,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/map_attribute/attributes.cfg b/config-model/src/test/derived/map_attribute/attributes.cfg
index 28cb551cced..4de78c52efd 100644
--- a/config-model/src/test/derived/map_attribute/attributes.cfg
+++ b/config-model/src/test/derived/map_attribute/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "str_map.value"
 attribute[].datatype STRING
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "int_map.key"
 attribute[].datatype INT32
@@ -69,4 +71,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/map_of_struct_attribute/attributes.cfg b/config-model/src/test/derived/map_of_struct_attribute/attributes.cfg
index caae49a0252..72e60b857a2 100644
--- a/config-model/src/test/derived/map_of_struct_attribute/attributes.cfg
+++ b/config-model/src/test/derived/map_of_struct_attribute/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "str_elem_map.value.name"
 attribute[].datatype STRING
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "str_elem_map.value.weight"
 attribute[].datatype INT32
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "int_elem_map.key"
 attribute[].datatype INT32
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "int_elem_map.value.name"
 attribute[].datatype STRING
@@ -117,4 +121,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/music/attributes.cfg b/config-model/src/test/derived/music/attributes.cfg
index a045a532965..4d19dc69b33 100644
--- a/config-model/src/test/derived/music/attributes.cfg
+++ b/config-model/src/test/derived/music/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "pto"
 attribute[].datatype INT32
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "mid"
 attribute[].datatype INT32
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "weight"
 attribute[].datatype FLOAT
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "bgnpfrom"
 attribute[].datatype FLOAT
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "newestedition"
 attribute[].datatype INT32
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "year"
 attribute[].datatype INT32
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "did"
 attribute[].datatype INT32
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "cbid"
 attribute[].datatype INT32
@@ -213,6 +221,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "hiphopvalue_arr"
 attribute[].datatype STRING
@@ -237,6 +246,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "metalvalue_arr"
 attribute[].datatype STRING
@@ -261,4 +271,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/newrank/attributes.cfg b/config-model/src/test/derived/newrank/attributes.cfg
index f728b1b1d33..2aed2288773 100644
--- a/config-model/src/test/derived/newrank/attributes.cfg
+++ b/config-model/src/test/derived/newrank/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "pto"
 attribute[].datatype INT32
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "mid"
 attribute[].datatype INT32
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "weight"
 attribute[].datatype FLOAT
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "bgnpfrom"
 attribute[].datatype FLOAT
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "newestedition"
 attribute[].datatype INT32
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "year"
 attribute[].datatype INT32
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "did"
 attribute[].datatype INT32
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "scorekey"
 attribute[].datatype INT32
@@ -213,6 +221,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "cbid"
 attribute[].datatype INT32
@@ -237,4 +246,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/predicate_attribute/attributes.cfg b/config-model/src/test/derived/predicate_attribute/attributes.cfg
index 458ee86031d..3a9daf7af94 100644
--- a/config-model/src/test/derived/predicate_attribute/attributes.cfg
+++ b/config-model/src/test/derived/predicate_attribute/attributes.cfg
@@ -21,4 +21,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/prefixexactattribute/attributes.cfg b/config-model/src/test/derived/prefixexactattribute/attributes.cfg
index 33fcecb1008..0a8cbd82186 100644
--- a/config-model/src/test/derived/prefixexactattribute/attributes.cfg
+++ b/config-model/src/test/derived/prefixexactattribute/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "attributefield2"
 attribute[].datatype STRING
@@ -45,4 +46,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/reference_fields/attributes.cfg b/config-model/src/test/derived/reference_fields/attributes.cfg
index 58125f73f9c..e83b187a0cc 100644
--- a/config-model/src/test/derived/reference_fields/attributes.cfg
+++ b/config-model/src/test/derived/reference_fields/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "other_ref"
 attribute[].datatype REFERENCE
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "yet_another_ref"
 attribute[].datatype REFERENCE
@@ -69,4 +71,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/sorting/attributes.cfg b/config-model/src/test/derived/sorting/attributes.cfg
index 3404d6a0384..83c310ca5ca 100644
--- a/config-model/src/test/derived/sorting/attributes.cfg
+++ b/config-model/src/test/derived/sorting/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "syntaxcheck2"
 attribute[].datatype STRING
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "infieldonly"
 attribute[].datatype STRING
@@ -69,4 +71,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/tensor/attributes.cfg b/config-model/src/test/derived/tensor/attributes.cfg
index a8531f73c1e..780f47ee3d5 100644
--- a/config-model/src/test/derived/tensor/attributes.cfg
+++ b/config-model/src/test/derived/tensor/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype "tensor<float>(x[2],y[1])"
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "f3"
 attribute[].datatype TENSOR
@@ -45,6 +46,7 @@ attribute[].tensortype "tensor(x{})"
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "f4"
 attribute[].datatype TENSOR
@@ -69,6 +71,7 @@ attribute[].tensortype "tensor(x[10],y[10])"
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "f5"
 attribute[].datatype TENSOR
@@ -93,6 +96,7 @@ attribute[].tensortype "tensor<float>(x[10])"
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "f6"
 attribute[].datatype FLOAT
@@ -117,4 +121,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/config-model/src/test/derived/types/attributes.cfg b/config-model/src/test/derived/types/attributes.cfg
index 290dd5b9a8b..82535324864 100644
--- a/config-model/src/test/derived/types/attributes.cfg
+++ b/config-model/src/test/derived/types/attributes.cfg
@@ -21,6 +21,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "along"
 attribute[].datatype INT64
@@ -45,6 +46,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "abool"
 attribute[].datatype BOOL
@@ -69,6 +71,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "ashortfloat"
 attribute[].datatype FLOAT16
@@ -93,6 +96,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "arrayfield"
 attribute[].datatype INT32
@@ -117,6 +121,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "setfield"
 attribute[].datatype STRING
@@ -141,6 +146,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "setfield2"
 attribute[].datatype STRING
@@ -165,6 +171,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "setfield3"
 attribute[].datatype STRING
@@ -189,6 +196,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "setfield4"
 attribute[].datatype STRING
@@ -213,6 +221,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "tagfield"
 attribute[].datatype STRING
@@ -237,6 +246,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "juletre"
 attribute[].datatype INT64
@@ -261,6 +271,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "album1"
 attribute[].datatype STRING
@@ -285,6 +296,7 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
 attribute[].name "other"
 attribute[].datatype INT64
@@ -309,4 +321,5 @@ attribute[].tensortype ""
 attribute[].imported false
 attribute[].index.hnsw.enabled false
 attribute[].index.hnsw.maxlinkspernode 16
+attribute[].index.hnsw.distancemetric EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert 200
diff --git a/configdefinitions/src/vespa/attributes.def b/configdefinitions/src/vespa/attributes.def
index eb7dad88995..604ddd40930 100644
--- a/configdefinitions/src/vespa/attributes.def
+++ b/configdefinitions/src/vespa/attributes.def
@@ -34,4 +34,5 @@ attribute[].imported           bool default=false
 # Configuration parameters for a hnsw index used together with a 1-dimensional indexed tensor for approximate nearest neighbor search.
 attribute[].index.hnsw.enabled bool default=false
 attribute[].index.hnsw.maxlinkspernode int default=16
+attribute[].index.hnsw.distancemetric enum { EUCLIDEAN, ANGULAR, GEODEGREES } default=EUCLIDEAN
 attribute[].index.hnsw.neighborstoexploreatinsert int default=200