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diff --git a/src/mongo/executor/connection_pool_controllers.cpp b/src/mongo/executor/connection_pool_controllers.cpp
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+++ b/src/mongo/executor/connection_pool_controllers.cpp
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+/**
+ *    Copyright (C) 2023-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 <algorithm>
+
+#include "mongo/executor/connection_pool_controllers.h"
+
+namespace mongo::executor {
+namespace {
+template <typename Map, typename Key>
+auto& getOrInvariant(Map&& map, const Key& key) {
+    auto it = map.find(key);
+    invariant(it != map.end(), "Unable to find key in map");
+
+    return it->second;
+}
+}  // namespace
+
+void DynamicLimitController::init(executor::ConnectionPool* parent) {
+    ControllerInterface::init(parent);
+}
+
+void DynamicLimitController::addHost(PoolId id, const HostAndPort& host) {
+    stdx::lock_guard lk(_mutex);
+    auto ret = _poolData.insert({id, {host}});
+    using namespace fmt::literals;
+    invariant(
+        ret.second,
+        "ConnectionPool controller {} received a request to track host {} that was already being tracked."_format(
+            _name, host));
+}
+
+DynamicLimitController::HostGroupState DynamicLimitController::updateHost(PoolId id,
+                                                                          const HostState& stats) {
+    stdx::lock_guard lk(_mutex);
+    auto& data = getOrInvariant(_poolData, id);
+    data.target =
+        std::clamp(stats.requests + stats.active + stats.leased, _minLoader(), _maxLoader());
+    return {{data.host}, stats.health.isExpired};
+}
+
+void DynamicLimitController::removeHost(PoolId id) {
+    stdx::lock_guard lk(_mutex);
+    invariant(_poolData.erase(id));
+}
+
+ConnectionPool::ConnectionControls DynamicLimitController::getControls(PoolId id) {
+    stdx::lock_guard lk(_mutex);
+    return {getPoolOptions().maxConnecting, getOrInvariant(_poolData, id).target};
+}
+
+}  // namespace mongo::executor