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diff --git a/src/mongo/util/container_size_helper.h b/src/mongo/util/container_size_helper.h
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+/**
+ *    Copyright (C) 2019-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <vector>
+
+namespace mongo {
+namespace container_size_helper {
+/**
+ * Returns the estimate of the number of bytes consumed by the vector, based on the current capacity
+ * of the vector and the size of objects of type T. Does not incorporate the size of any owned
+ * objects that are pointed to by T. Also, does not incorporate sizeof(vector).
+ */
+template <class T>
+uint64_t estimateObjectSizeInBytes(const std::vector<T>& vector) {
+    return static_cast<uint64_t>(vector.capacity()) * sizeof(T);
+}
+
+/**
+ * Returns the estimate of the number of bytes consumed by the container, based on the current
+ * capacity of the container and the size of objects of type 'T::value_type'. Does not incorporate
+ * the size of any owned objects that are pointed to by 'T::value_type'. Also, does not incorporate
+ * sizeof(container).
+ */
+template <class T>
+uint64_t estimateObjectSizeInBytes(const T& container) {
+    return static_cast<uint64_t>(container.size()) * sizeof(typename T::value_type);
+}
+
+/**
+ * Returns the estimate by recursively calculating the memory owned by each element of the
+ * container. The 'function' should calculate the overall size of each individual element of the
+ * 'container'.
+ * When 'includeShallowSize' is true, adds the size of each container element.
+ */
+template <class T, class Function>
+uint64_t estimateObjectSizeInBytes(const T& container, Function function, bool includeShallowSize) {
+    uint64_t result = 0;
+    for (const auto& element : container) {
+        result += function(element);
+    }
+    result += includeShallowSize ? estimateObjectSizeInBytes(container) : 0;
+    return result;
+}
+}  // namespace container_size_helper
+}  // namespace mongo