4 files changed, 99 insertions, 7 deletions

diff --git a/src/mongo/executor/SConscript b/src/mongo/executor/SConscript
index 5ff35f0db4d..815159efd70 100644
--- a/src/mongo/executor/SConscript
+++ b/src/mongo/executor/SConscript
@@ -318,6 +318,7 @@ env.CppUnitTest(
         'mock_remote_command_runner_test.cpp',
         'network_interface_mock_test.cpp',
         'network_interface_mock_test_fixture.cpp',
+        'network_interface_tl_test.cpp',
         'remote_command_runner_test.cpp',
         'scoped_task_executor_test.cpp',
         'task_executor_cursor_test.cpp',
@@ -332,6 +333,7 @@ env.CppUnitTest(
         'connection_pool_executor',
         'egress_tag_closer_manager',
         'network_interface_mock',
+        'network_interface_tl',
         'network_test_env',
         'remote_command_runner',
         'scoped_task_executor',
diff --git a/src/mongo/executor/network_interface_tl.cpp b/src/mongo/executor/network_interface_tl.cpp
index 6b3aab3f26a..f6979f18462 100644
--- a/src/mongo/executor/network_interface_tl.cpp
+++ b/src/mongo/executor/network_interface_tl.cpp
@@ -115,6 +115,17 @@ bool skipHedgeResult(const Status& status) {
         ErrorCodes::isNetworkTimeoutError(status) || ErrorCodes::isStaleShardVersionError(status);
 }
 
+template <typename IA, typename IB, typename F>
+int compareTransformed(IA a1, IA a2, IB b1, IB b2, F&& f) {
+    for (;; ++a1, ++b1)
+        if (a1 == a2)
+            return b1 == b2 ? 0 : -1;
+        else if (b1 == b2)
+            return 1;
+        else if (int r = f(*a1) - f(*b1))
+            return r;
+}
+
 }  // namespace
 
 /**
@@ -572,15 +583,12 @@ Status NetworkInterfaceTL::startCommand(const TaskExecutor::CallbackHandle& cbHa
 
     bool targetHostsInAlphabeticalOrder =
         MONGO_unlikely(networkInterfaceSendRequestsToTargetHostsInAlphabeticalOrder.shouldFail(
-            [request](const BSONObj&) { return request.options.isHedgeEnabled; }));
+            [&](const BSONObj&) { return request.options.isHedgeEnabled; }));
 
     if (targetHostsInAlphabeticalOrder) {
-        // Sort the target hosts by host names.
-        std::sort(request.target.begin(),
-                  request.target.end(),
-                  [](const HostAndPort& target1, const HostAndPort& target2) {
-                      return target1.toString() < target2.toString();
-                  });
+        std::sort(request.target.begin(), request.target.end(), [](auto&& a, auto&& b) {
+            return detail::orderByLowerHostThenPort(a, b);
+        });
     }
 
     if ((request.target.size() > 1) && !request.options.isHedgeEnabled &&
@@ -1387,5 +1395,17 @@ void NetworkInterfaceTL::dropConnections(const HostAndPort& hostAndPort) {
     _pool->dropConnections(hostAndPort);
 }
 
+namespace detail {
+
+bool orderByLowerHostThenPort(const HostAndPort& a, const HostAndPort& b) {
+    const auto& ah = a.host();
+    const auto& bh = b.host();
+    if (int r = compareTransformed(
+            ah.begin(), ah.end(), bh.begin(), bh.end(), [](auto&& c) { return ctype::toLower(c); }))
+        return r < 0;
+    return a.port() < b.port();
+}
+
+}  // namespace detail
 }  // namespace executor
 }  // namespace mongo
diff --git a/src/mongo/executor/network_interface_tl.h b/src/mongo/executor/network_interface_tl.h
index fefb300f6fe..7353c92cd26 100644
--- a/src/mongo/executor/network_interface_tl.h
+++ b/src/mongo/executor/network_interface_tl.h
@@ -395,5 +395,11 @@ private:
     bool _isExecutorRunnable = false;
 };
 
+namespace detail {
+
+/** Order HostAndPorts by their lowercased hostnames then port number */
+bool orderByLowerHostThenPort(const HostAndPort& a, const HostAndPort& b);
+
+}  // namespace detail
 }  // namespace executor
 }  // namespace mongo
diff --git a/src/mongo/executor/network_interface_tl_test.cpp b/src/mongo/executor/network_interface_tl_test.cpp
new file mode 100644
index 00000000000..06bafcbafe3
--- /dev/null
+++ b/src/mongo/executor/network_interface_tl_test.cpp
@@ -0,0 +1,64 @@
+/**
+ *    Copyright (C) 2022-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/executor/network_interface_tl.h"
+#include "mongo/unittest/unittest.h"
+#include "mongo/util/net/hostandport.h"
+
+namespace mongo {
+namespace executor {
+namespace {
+
+TEST(NetworkInterfaceTL, HostAndPortSorting) {
+    struct Spec {
+        HostAndPort a;
+        HostAndPort b;
+        bool out;
+    };
+    static const Spec specs[]{
+        {HostAndPort("ABC"), HostAndPort("abb"), false},
+        {HostAndPort("abc"), HostAndPort("abcd"), true},
+        {HostAndPort("abc", 1), HostAndPort("abc", 2), true},
+        {HostAndPort("de:35"), HostAndPort("de:32"), false},
+        {HostAndPort("def:34"), HostAndPort("dEF:39"), true},
+        {HostAndPort("[0:0:0]"), HostAndPort("abc"), true},
+        {HostAndPort("[0:0:0]"), HostAndPort("ABC"), true},
+    };
+    for (const auto& [a, b, out] : specs) {
+        ASSERT_EQ(detail::orderByLowerHostThenPort(a, b), out) << ", a:" << a << ", b:" << b;
+        if (out) {
+            ASSERT_EQ(detail::orderByLowerHostThenPort(b, a), !out) << ", a:" << a << ", b:" << b;
+        }
+    }
+}
+
+}  // namespace
+}  // namespace executor
+}  // namespace mongo