[DRAFT] Change vector input from IndexInput to RandomAccessInput

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/store/EndiannessReverserIndexInput.java

@@ -63,8 +63,7 @@ public void readInts(int[] dst, int offset, int length) throws IOException {
   public void readFloats(float[] dst, int offset, int length) throws IOException {
     in.readFloats(dst, offset, length);
     for (int i = 0; i < length; ++i) {
-      dst[offset + i] =
-          Float.intBitsToFloat(Integer.reverseBytes(Float.floatToRawIntBits(dst[offset + i])));
+      dst[offset + i] = revertFloat(dst[offset + i]);
     }
   }
 
@@ -106,6 +105,14 @@ public byte readByte(long pos) throws IOException {
       return in.readByte(pos);
     }
 
+    @Override
+    public void readFloats(long pos, float[] floats, int offset, int length) throws IOException {
+      in.readFloats(pos, floats, offset, length);
+      for (int i = 0; i < length; ++i) {
+        floats[offset + i] = revertFloat(floats[offset + i]);
+      }
+    }
+
     @Override
     public short readShort(long pos) throws IOException {
       return Short.reverseBytes(in.readShort(pos));
@@ -120,5 +127,19 @@ public int readInt(long pos) throws IOException {
     public long readLong(long pos) throws IOException {
       return Long.reverseBytes(in.readLong(pos));
     }
+
+    @Override
+    public Object clone() {
+      try {
+        return super.clone();
+      } catch (CloneNotSupportedException e) {
+        throw new Error(
+            "This cannot happen: Failing to clone EndiannessReverserRandomAccessInput", e);
+      }
+    }
+  }
+
+  private static float revertFloat(float value) {
+    return Float.intBitsToFloat(Integer.reverseBytes(Float.floatToRawIntBits(value)));
   }
 }

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene95/Lucene95HnswVectorsWriter.java

@@ -450,7 +450,7 @@ public void mergeOneField(FieldInfo fieldInfo, MergeState mergeState) throws IOE
                     new OffHeapByteVectorValues.DenseOffHeapVectorValues(
                         fieldInfo.getVectorDimension(),
                         docsWithField.cardinality(),
-                        vectorDataInput,
+                        vectorDataInput.toRandomAccessInput(),
                         byteSize,
                         defaultFlatVectorScorer,
                         fieldInfo.getVectorSimilarityFunction()));
@@ -462,7 +462,7 @@ public void mergeOneField(FieldInfo fieldInfo, MergeState mergeState) throws IOE
                     new OffHeapFloatVectorValues.DenseOffHeapVectorValues(
                         fieldInfo.getVectorDimension(),
                         docsWithField.cardinality(),
-                        vectorDataInput,
+                        vectorDataInput.toRandomAccessInput(),
                         byteSize,
                         defaultFlatVectorScorer,
                         fieldInfo.getVectorSimilarityFunction()));

lucene/benchmark-jmh/src/java/org/apache/lucene/benchmark/jmh/VectorScorerBenchmark.java

@@ -98,7 +98,7 @@ public float binaryDotProductMemSeg() throws IOException {
   static KnnVectorValues vectorValues(
       int dims, int size, IndexInput in, VectorSimilarityFunction sim) throws IOException {
     return new OffHeapByteVectorValues.DenseOffHeapVectorValues(
-        dims, size, in.slice("test", 0, in.length()), dims, new ThrowingFlatVectorScorer(), sim);
+        dims, size, in.toRandomAccessInput(), dims, new ThrowingFlatVectorScorer(), sim);
   }
 
   static final class ThrowingFlatVectorScorer implements FlatVectorsScorer {

lucene/core/src/java/org/apache/lucene/codecs/lucene95/HasIndexSlice.java

@@ -16,14 +16,14 @@
  */
 package org.apache.lucene.codecs.lucene95;
 
-import org.apache.lucene.store.IndexInput;
+import org.apache.lucene.store.RandomAccessInput;
 
 /**
- * Implementors can return the IndexInput from which their values are read. For use by vector
+ * Implementors can return the RandomAccessInput from which their values are read. For use by vector
  * quantizers.
  */
 public interface HasIndexSlice {
 
-  /** Returns an IndexInput from which to read this instance's values. */
-  IndexInput getSlice();
+  /** Returns a RandomAccessInput from which to read this instance's values. */
+  RandomAccessInput getSlice();
 }

lucene/core/src/java/org/apache/lucene/codecs/lucene95/OffHeapByteVectorValues.java

@@ -37,7 +37,7 @@ public abstract class OffHeapByteVectorValues extends ByteVectorValues implement
 
   protected final int dimension;
   protected final int size;
-  protected final IndexInput slice;
+  protected final RandomAccessInput slice;
   protected int lastOrd = -1;
   protected final byte[] binaryValue;
   protected final ByteBuffer byteBuffer;
@@ -48,7 +48,7 @@ public abstract class OffHeapByteVectorValues extends ByteVectorValues implement
   OffHeapByteVectorValues(
       int dimension,
       int size,
-      IndexInput slice,
+      RandomAccessInput slice,
       int byteSize,
       FlatVectorsScorer flatVectorsScorer,
       VectorSimilarityFunction similarityFunction) {
@@ -82,13 +82,13 @@ public byte[] vectorValue(int targetOrd) throws IOException {
   }
 
   @Override
-  public IndexInput getSlice() {
+  public RandomAccessInput getSlice() {
     return slice;
   }
 
   private void readValue(int targetOrd) throws IOException {
-    slice.seek((long) targetOrd * byteSize);
-    slice.readBytes(byteBuffer.array(), byteBuffer.arrayOffset(), byteSize);
+    slice.readBytes(
+        (long) targetOrd * byteSize, byteBuffer.array(), byteBuffer.arrayOffset(), byteSize);
   }
 
   public static OffHeapByteVectorValues load(
@@ -104,7 +104,7 @@ public static OffHeapByteVectorValues load(
     if (configuration.isEmpty() || vectorEncoding != VectorEncoding.BYTE) {
       return new EmptyOffHeapVectorValues(dimension, flatVectorsScorer, vectorSimilarityFunction);
     }
-    IndexInput bytesSlice = vectorData.slice("vector-data", vectorDataOffset, vectorDataLength);
+    RandomAccessInput bytesSlice = vectorData.randomAccessSlice(vectorDataOffset, vectorDataLength);
     if (configuration.isDense()) {
       return new DenseOffHeapVectorValues(
           dimension,
@@ -133,7 +133,7 @@ public static class DenseOffHeapVectorValues extends OffHeapByteVectorValues {
     public DenseOffHeapVectorValues(
         int dimension,
         int size,
-        IndexInput slice,
+        RandomAccessInput slice,
         int byteSize,
         FlatVectorsScorer flatVectorsScorer,
         VectorSimilarityFunction vectorSimilarityFunction) {
@@ -143,7 +143,12 @@ public DenseOffHeapVectorValues(
     @Override
     public DenseOffHeapVectorValues copy() throws IOException {
       return new DenseOffHeapVectorValues(
-          dimension, size, slice.clone(), byteSize, flatVectorsScorer, similarityFunction);
+          dimension,
+          size,
+          (RandomAccessInput) slice.clone(),
+          byteSize,
+          flatVectorsScorer,
+          similarityFunction);
     }
 
     @Override
@@ -186,7 +191,7 @@ private static class SparseOffHeapVectorValues extends OffHeapByteVectorValues {
     public SparseOffHeapVectorValues(
         OrdToDocDISIReaderConfiguration configuration,
         IndexInput dataIn,
-        IndexInput slice,
+        RandomAccessInput slice,
         int dimension,
         int byteSize,
         FlatVectorsScorer flatVectorsScorer,
@@ -220,7 +225,7 @@ public SparseOffHeapVectorValues copy() throws IOException {
       return new SparseOffHeapVectorValues(
           configuration,
           dataIn,
-          slice.clone(),
+          (RandomAccessInput) slice.clone(),
           dimension,
           byteSize,
           flatVectorsScorer,

lucene/core/src/java/org/apache/lucene/codecs/lucene95/OffHeapFloatVectorValues.java

@@ -36,7 +36,7 @@ public abstract class OffHeapFloatVectorValues extends FloatVectorValues impleme
 
   protected final int dimension;
   protected final int size;
-  protected final IndexInput slice;
+  protected final RandomAccessInput slice;
   protected final int byteSize;
   protected int lastOrd = -1;
   protected final float[] value;
@@ -46,7 +46,7 @@ public abstract class OffHeapFloatVectorValues extends FloatVectorValues impleme
   OffHeapFloatVectorValues(
       int dimension,
       int size,
-      IndexInput slice,
+      RandomAccessInput slice,
       int byteSize,
       FlatVectorsScorer flatVectorsScorer,
       VectorSimilarityFunction similarityFunction) {
@@ -70,7 +70,7 @@ public int size() {
   }
 
   @Override
-  public IndexInput getSlice() {
+  public RandomAccessInput getSlice() {
     return slice;
   }
 
@@ -79,8 +79,7 @@ public float[] vectorValue(int targetOrd) throws IOException {
     if (lastOrd == targetOrd) {
       return value;
     }
-    slice.seek((long) targetOrd * byteSize);
-    slice.readFloats(value, 0, value.length);
+    slice.readFloats((long) targetOrd * byteSize, value, 0, value.length);
     lastOrd = targetOrd;
     return value;
   }
@@ -98,7 +97,7 @@ public static OffHeapFloatVectorValues load(
     if (configuration.docsWithFieldOffset == -2 || vectorEncoding != VectorEncoding.FLOAT32) {
       return new EmptyOffHeapVectorValues(dimension, flatVectorsScorer, vectorSimilarityFunction);
     }
-    IndexInput bytesSlice = vectorData.slice("vector-data", vectorDataOffset, vectorDataLength);
+    RandomAccessInput bytesSlice = vectorData.randomAccessSlice(vectorDataOffset, vectorDataLength);
     int byteSize = dimension * Float.BYTES;
     if (configuration.docsWithFieldOffset == -1) {
       return new DenseOffHeapVectorValues(
@@ -129,7 +128,7 @@ public static class DenseOffHeapVectorValues extends OffHeapFloatVectorValues {
     public DenseOffHeapVectorValues(
         int dimension,
         int size,
-        IndexInput slice,
+        RandomAccessInput slice,
         int byteSize,
         FlatVectorsScorer flatVectorsScorer,
         VectorSimilarityFunction similarityFunction) {
@@ -139,7 +138,12 @@ public DenseOffHeapVectorValues(
     @Override
     public DenseOffHeapVectorValues copy() throws IOException {
       return new DenseOffHeapVectorValues(
-          dimension, size, slice.clone(), byteSize, flatVectorsScorer, similarityFunction);
+          dimension,
+          size,
+          (RandomAccessInput) slice.clone(),
+          byteSize,
+          flatVectorsScorer,
+          similarityFunction);
     }
 
     @Override
@@ -187,7 +191,7 @@ private static class SparseOffHeapVectorValues extends OffHeapFloatVectorValues
     public SparseOffHeapVectorValues(
         OrdToDocDISIReaderConfiguration configuration,
         IndexInput dataIn,
-        IndexInput slice,
+        RandomAccessInput slice,
         int dimension,
         int byteSize,
         FlatVectorsScorer flatVectorsScorer,
@@ -215,7 +219,7 @@ public SparseOffHeapVectorValues copy() throws IOException {
       return new SparseOffHeapVectorValues(
           configuration,
           dataIn,
-          slice.clone(),
+          (RandomAccessInput) slice.clone(),
           dimension,
           byteSize,
           flatVectorsScorer,

lucene/core/src/java/org/apache/lucene/codecs/lucene99/Lucene99FlatVectorsWriter.java

@@ -303,7 +303,7 @@ public CloseableRandomVectorScorerSupplier mergeOneFieldToIndex(
                     new OffHeapByteVectorValues.DenseOffHeapVectorValues(
                         fieldInfo.getVectorDimension(),
                         docsWithField.cardinality(),
-                        finalVectorDataInput,
+                        finalVectorDataInput.toRandomAccessInput(),
                         fieldInfo.getVectorDimension() * Byte.BYTES,
                         vectorsScorer,
                         fieldInfo.getVectorSimilarityFunction()));
@@ -313,7 +313,7 @@ public CloseableRandomVectorScorerSupplier mergeOneFieldToIndex(
                     new OffHeapFloatVectorValues.DenseOffHeapVectorValues(
                         fieldInfo.getVectorDimension(),
                         docsWithField.cardinality(),
-                        finalVectorDataInput,
+                        finalVectorDataInput.toRandomAccessInput(),
                         fieldInfo.getVectorDimension() * Float.BYTES,
                         vectorsScorer,
                         fieldInfo.getVectorSimilarityFunction()));

lucene/core/src/java/org/apache/lucene/codecs/lucene99/Lucene99ScalarQuantizedVectorScorer.java

@@ -213,8 +213,8 @@ private CompressedInt4DotProduct(
     public float score(int vectorOrdinal) throws IOException {
       // get compressed vector, in Lucene99, vector values are stored and have a single value for
       // offset correction
-      values.getSlice().seek((long) vectorOrdinal * (values.getVectorByteLength() + Float.BYTES));
-      values.getSlice().readBytes(compressedVector, 0, compressedVector.length);
+      long pos = (long) vectorOrdinal * (values.getVectorByteLength() + Float.BYTES);
+      values.getSlice().readBytes(pos, compressedVector, 0, compressedVector.length);
       float vectorOffset = values.getScoreCorrectionConstant(vectorOrdinal);
       int dotProduct = VectorUtil.int4DotProductPacked(targetBytes, compressedVector);
       // For the current implementation of scalar quantization, all dotproducts should be >= 0;

lucene/core/src/java/org/apache/lucene/codecs/lucene99/Lucene99ScalarQuantizedVectorsWriter.java

@@ -524,7 +524,7 @@ private ScalarQuantizedCloseableRandomVectorScorerSupplier mergeOneFieldToIndex(
                   compress,
                   fieldInfo.getVectorSimilarityFunction(),
                   vectorsScorer,
-                  quantizationDataInput)));
+                  quantizationDataInput.toRandomAccessInput())));
     } finally {
       if (success == false) {
         IOUtils.closeWhileHandlingException(tempQuantizedVectorData, quantizationDataInput);