1 files changed, 48 insertions, 13 deletions

diff --git a/src/mongo/db/mirror_maestro.cpp b/src/mongo/db/mirror_maestro.cpp
index 31d9de386d9..7f898db664d 100644
--- a/src/mongo/db/mirror_maestro.cpp
+++ b/src/mongo/db/mirror_maestro.cpp
@@ -41,6 +41,7 @@
 #include "mongo/bson/bsonelement.h"
 #include "mongo/bson/bsonobjbuilder.h"
 #include "mongo/bson/json.h"
+#include "mongo/db/client_out_of_line_executor.h"
 #include "mongo/db/commands.h"
 #include "mongo/db/commands/server_status.h"
 #include "mongo/db/mirror_maestro_gen.h"
@@ -90,15 +91,43 @@ public:
      */
     void tryMirror(std::shared_ptr<CommandInvocation> invocation) noexcept;
 
+    /**
+     * Maintains the state required for mirroring requests.
+     */
+    class MirroredRequestState {
+    public:
+        MirroredRequestState(MirrorMaestroImpl* maestro,
+                             std::vector<HostAndPort> hosts,
+                             std::shared_ptr<CommandInvocation> invocation,
+                             MirroredReadsParameters params)
+            : _maestro(std::move(maestro)),
+              _hosts(std::move(hosts)),
+              _invocation(std::move(invocation)),
+              _params(std::move(params)) {}
+
+        MirroredRequestState() = delete;
+
+        void mirror() noexcept {
+            invariant(_maestro);
+            _maestro->_mirror(_hosts, _invocation, _params);
+        }
+
+    private:
+        MirrorMaestroImpl* _maestro;
+        std::vector<HostAndPort> _hosts;
+        std::shared_ptr<CommandInvocation> _invocation;
+        MirroredReadsParameters _params;
+    };
+
 private:
     /**
      * Attempt to mirror invocation to a subset of hosts based on params
      *
      * This command is expected to only run on the _executor
      */
-    void _mirror(std::vector<HostAndPort> hosts,
+    void _mirror(const std::vector<HostAndPort>& hosts,
                  std::shared_ptr<CommandInvocation> invocation,
-                 MirroredReadsParameters params) noexcept;
+                 const MirroredReadsParameters& params) noexcept;
 
     /**
      * An enum detailing the liveness of the Maestro
@@ -256,26 +285,32 @@ void MirrorMaestroImpl::tryMirror(std::shared_ptr<CommandInvocation> invocation)
         return;
     }
 
+    auto clientExecutor = ClientOutOfLineExecutor::get(Client::getCurrent());
+    auto clientExecutorHandle = clientExecutor->getHandle();
+
+    // TODO SERVER-46619 delegates collection to the client's baton
+    clientExecutor->consumeAllTasks();
+
     // There is the potential to actually mirror requests, so schedule the _mirror() invocation
     // out-of-line. This means the command itself can return quickly and we do the arduous work of
     // building new bsons and evaluating randomness in a less important context.
+    auto requestState = std::make_unique<MirroredRequestState>(
+        this, std::move(hosts), std::move(invocation), std::move(params));
     ExecutorFuture(_executor)  //
-        .getAsync([this,
-                   hosts = std::move(hosts),
-                   invocation = std::move(invocation),
-                   params = std::move(params)](const auto& status) mutable {
-            if (ErrorCodes::isShutdownError(status)) {
-                return;
+        .getAsync([clientExecutorHandle,
+                   requestState = std::move(requestState)](const auto& status) mutable {
+            if (!ErrorCodes::isShutdownError(status)) {
+                invariant(status.isOK());
+                requestState->mirror();
             }
-            invariant(status.isOK());
-
-            _mirror(std::move(hosts), std::move(invocation), std::move(params));
+            clientExecutorHandle.schedule([requestState = std::move(requestState)](
+                                              const Status&) mutable { requestState.reset(); });
         });
 }
 
-void MirrorMaestroImpl::_mirror(std::vector<HostAndPort> hosts,
+void MirrorMaestroImpl::_mirror(const std::vector<HostAndPort>& hosts,
                                 std::shared_ptr<CommandInvocation> invocation,
-                                MirroredReadsParameters params) noexcept try {
+                                const MirroredReadsParameters& params) noexcept try {
     auto payload = [&] {
         BSONObjBuilder bob;