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diff --git a/src/main/java/org/elasticsearch/common/util/BigDoubleArray.java b/src/main/java/org/elasticsearch/common/util/BigDoubleArray.java
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+++ b/src/main/java/org/elasticsearch/common/util/BigDoubleArray.java
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+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.common.util;
+
+import com.google.common.base.Preconditions;
+import org.apache.lucene.util.ArrayUtil;
+import org.apache.lucene.util.RamUsageEstimator;
+import org.elasticsearch.cache.recycler.PageCacheRecycler;
+
+import java.util.Arrays;
+
+import static org.elasticsearch.common.util.BigArrays.DOUBLE_PAGE_SIZE;
+
+/**
+ * Double array abstraction able to support more than 2B values. This implementation slices data into fixed-sized blocks of
+ * configurable length.
+ */
+final class BigDoubleArray extends AbstractBigArray implements DoubleArray {
+
+    private double[][] pages;
+
+    /** Constructor. */
+    public BigDoubleArray(long size, PageCacheRecycler recycler, boolean clearOnResize) {
+        super(DOUBLE_PAGE_SIZE, recycler, clearOnResize);
+        this.size = size;
+        pages = new double[numPages(size)][];
+        for (int i = 0; i < pages.length; ++i) {
+            pages[i] = newDoublePage(i);
+        }
+    }
+
+    @Override
+    public double get(long index) {
+        final int pageIndex = pageIndex(index);
+        final int indexInPage = indexInPage(index);
+        return pages[pageIndex][indexInPage];
+    }
+
+    @Override
+    public double set(long index, double value) {
+        final int pageIndex = pageIndex(index);
+        final int indexInPage = indexInPage(index);
+        final double[] page = pages[pageIndex];
+        final double ret = page[indexInPage];
+        page[indexInPage] = value;
+        return ret;
+    }
+
+    @Override
+    public double increment(long index, double inc) {
+        final int pageIndex = pageIndex(index);
+        final int indexInPage = indexInPage(index);
+        return pages[pageIndex][indexInPage] += inc;
+    }
+
+    @Override
+    protected int numBytesPerElement() {
+        return RamUsageEstimator.NUM_BYTES_INT;
+    }
+
+    /** Change the size of this array. Content between indexes <code>0</code> and <code>min(size(), newSize)</code> will be preserved. */
+    public void resize(long newSize) {
+        final int numPages = numPages(newSize);
+        if (numPages > pages.length) {
+            pages = Arrays.copyOf(pages, ArrayUtil.oversize(numPages, RamUsageEstimator.NUM_BYTES_OBJECT_REF));
+        }
+        for (int i = numPages - 1; i >= 0 && pages[i] == null; --i) {
+            pages[i] = newDoublePage(i);
+        }
+        for (int i = numPages; i < pages.length && pages[i] != null; ++i) {
+            pages[i] = null;
+            releasePage(i);
+        }
+        this.size = newSize;
+    }
+
+    @Override
+    public void fill(long fromIndex, long toIndex, double value) {
+        Preconditions.checkArgument(fromIndex <= toIndex);
+        final int fromPage = pageIndex(fromIndex);
+        final int toPage = pageIndex(toIndex - 1);
+        if (fromPage == toPage) {
+            Arrays.fill(pages[fromPage], indexInPage(fromIndex), indexInPage(toIndex - 1) + 1, value);
+        } else {
+            Arrays.fill(pages[fromPage], indexInPage(fromIndex), pages[fromPage].length, value);
+            for (int i = fromPage + 1; i < toPage; ++i) {
+                Arrays.fill(pages[i], value);
+            }
+            Arrays.fill(pages[toPage], 0, indexInPage(toIndex - 1) + 1, value);
+        }
+    }
+
+}