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diff --git a/src/mongo/s/client/num_hosts_targeted_metrics.cpp b/src/mongo/s/client/num_hosts_targeted_metrics.cpp
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+++ b/src/mongo/s/client/num_hosts_targeted_metrics.cpp
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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.
+ */
+
+#include "mongo/s/client/num_hosts_targeted_metrics.h"
+
+#include "mongo/base/init.h"
+#include "mongo/bson/bsonobjbuilder.h"
+#include "mongo/db/curop.h"
+#include "mongo/db/operation_context.h"
+#include "mongo/db/service_context.h"
+#include "mongo/s/grid.h"
+
+namespace mongo {
+
+const auto getNumHostsTargeted = ServiceContext::declareDecoration<NumHostsTargetedMetrics>();
+
+namespace {
+std::string queryTypeToString(NumHostsTargetedMetrics::QueryType queryType) {
+    switch (queryType) {
+        case NumHostsTargetedMetrics::QueryType::kFindCmd:
+            return "find";
+        case NumHostsTargetedMetrics::QueryType::kInsertCmd:
+            return "insert";
+        case NumHostsTargetedMetrics::QueryType::kUpdateCmd:
+            return "update";
+        case NumHostsTargetedMetrics::QueryType::kDeleteCmd:
+            return "delete";
+        case NumHostsTargetedMetrics::QueryType::kAggregateCmd:
+            return "aggregate";
+        default:
+            return "";
+    }
+}
+}  // namespace
+
+void NumHostsTargetedMetrics::addNumHostsTargeted(NumHostsTargetedMetrics::QueryType queryType,
+                                                  NumHostsTargetedMetrics::TargetType targetType) {
+    switch (targetType) {
+        case TargetType::kAllShards:
+            _numHostsTargeted[queryType]->allShards.addAndFetch(1);
+            return;
+        case TargetType::kManyShards:
+            _numHostsTargeted[queryType]->manyShards.addAndFetch(1);
+            return;
+        case TargetType::kOneShard:
+            _numHostsTargeted[queryType]->oneShard.addAndFetch(1);
+            return;
+        case TargetType::kUnsharded:
+            _numHostsTargeted[queryType]->unsharded.addAndFetch(1);
+            return;
+    }
+}
+
+void NumHostsTargetedMetrics::appendSection(BSONObjBuilder* builder) {
+    BSONObjBuilder numHostsTargetedStatsBuilder(builder->subobjStart("numHostsTargeted"));
+    for (auto i = 0; i < kNumQueryType; i++) {
+        auto& targetStat = _numHostsTargeted[i];
+        auto queryType = static_cast<QueryType>(i);
+        BSONObjBuilder queryStatsBuilder(
+            numHostsTargetedStatsBuilder.subobjStart(queryTypeToString(queryType)));
+        queryStatsBuilder.appendNumber("allShards", targetStat->allShards.load());
+        queryStatsBuilder.appendNumber("manyShards", targetStat->manyShards.load());
+        queryStatsBuilder.appendNumber("oneShard", targetStat->oneShard.load());
+        queryStatsBuilder.appendNumber("unsharded", targetStat->unsharded.load());
+    }
+}
+
+NumHostsTargetedMetrics::TargetType NumHostsTargetedMetrics::parseTargetType(
+    OperationContext* opCtx, int nShardsTargeted, int nShardsOwningChunks) {
+    // If nShardsOwningChunks == 0, this means the routing info did not contain a chunk manager so
+    // the collection is unsharded
+    if (nShardsOwningChunks == 0)
+        return TargetType::kUnsharded;
+
+    if (nShardsTargeted == 1)
+        return TargetType::kOneShard;
+
+    // If an update or delete targets > 1 shard, it will be broadcast to all shards in the cluster
+    // *regardless* of whether the shard owns any data for that collection. We should count this as
+    // 'allShards'.
+    if (nShardsTargeted >= nShardsOwningChunks)
+        return TargetType::kAllShards;
+
+    return TargetType::kManyShards;
+}
+
+NumHostsTargetedMetrics& NumHostsTargetedMetrics::get(ServiceContext* serviceContext) {
+    return getNumHostsTargeted(serviceContext);
+}
+
+NumHostsTargetedMetrics& NumHostsTargetedMetrics::get(OperationContext* opCtx) {
+    return get(opCtx->getServiceContext());
+}
+
+void NumHostsTargetedMetrics::startup() {
+    _numHostsTargeted.reserve(kNumQueryType);
+    for (auto i = 0; i < kNumQueryType; i++) {
+        _numHostsTargeted.push_back(std::make_unique<TargetStats>());
+    }
+}
+
+}  // namespace mongo