Revert "SERVER-65831 Use ScopedTaskExecutor to speed up BalancerCommandsScheduler stop()"

This reverts commit 00275096d675702c749a7cac59ca29d6532a5d7d.

2 files changed, 12 insertions, 21 deletions

diff --git a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.cpp b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.cpp
index 1234acfa6b0..797d4c00bbc 100644
--- a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.cpp
+++ b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.cpp
@@ -175,8 +175,7 @@ void BalancerCommandsSchedulerImpl::start(OperationContext* opCtx,
     stdx::lock_guard<Latch> lg(_mutex);
     invariant(!_workerThreadHandle.joinable());
     if (!_executor) {
-        _executor = std::make_unique<executor::ScopedTaskExecutor>(
-            Grid::get(opCtx)->getExecutorPool()->getFixedExecutor());
+        _executor = Grid::get(opCtx)->getExecutorPool()->getFixedExecutor();
     }
     auto requestsToRecover = rebuildRequestsFromRecoveryInfo(opCtx, defaultValues);
     _numRequestsToRecover = requestsToRecover.size();
@@ -421,7 +420,7 @@ CommandSubmissionResult BalancerCommandsSchedulerImpl::_submit(
     }
 
     auto swRemoteCommandHandle =
-        (*_executor)->scheduleRemoteCommand(remoteCommand, onRemoteResponseReceived);
+        _executor->scheduleRemoteCommand(remoteCommand, onRemoteResponseReceived);
     return CommandSubmissionResult(params.id, distLockTaken, swRemoteCommandHandle.getStatus());
 }
 
@@ -466,8 +465,7 @@ void BalancerCommandsSchedulerImpl::_applyCommandResponse(
 
 void BalancerCommandsSchedulerImpl::_performDeferredCleanup(
     OperationContext* opCtx,
-    const stdx::unordered_map<UUID, RequestData, UUID::Hash>& requestsHoldingResources,
-    bool includePersistedData) {
+    const stdx::unordered_map<UUID, RequestData, UUID::Hash>& requestsHoldingResources) {
     if (requestsHoldingResources.empty()) {
         return;
     }
@@ -477,7 +475,7 @@ void BalancerCommandsSchedulerImpl::_performDeferredCleanup(
         if (request.holdsDistributedLock()) {
             _distributedLocks.releaseFor(opCtx, request.getNamespace());
         }
-        if (includePersistedData && request.requiresRecoveryCleanupOnCompletion()) {
+        if (request.requiresRecoveryCleanupOnCompletion()) {
             deletePersistedRecoveryInfo(dbClient, request.getCommandInfo());
         }
     }
@@ -539,8 +537,7 @@ void BalancerCommandsSchedulerImpl::_workerThread() {
         // 2.a Free any resource acquired by already completed/aborted requests.
         {
             auto opCtxHolder = cc().makeOperationContext();
-            _performDeferredCleanup(
-                opCtxHolder.get(), completedRequestsToCleanUp, true /*includePersistedData*/);
+            _performDeferredCleanup(opCtxHolder.get(), completedRequestsToCleanUp);
             completedRequestsToCleanUp.clear();
         }
 
@@ -568,21 +565,17 @@ void BalancerCommandsSchedulerImpl::_workerThread() {
         }
     }
     // Wait for each outstanding command to complete, clean out its resources and leave.
-    (*_executor)->shutdown();
-    (*_executor)->join();
-
-    stdx::unordered_map<UUID, RequestData, UUID::Hash> cancelledRequests;
+    stdx::unordered_map<UUID, RequestData, UUID::Hash> requestsToClean;
     {
         stdx::unique_lock<Latch> ul(_mutex);
-        cancelledRequests.swap(_requests);
+        _stateUpdatedCV.wait(
+            ul, [this] { return (_requests.size() == _recentlyCompletedRequestIds.size()); });
+        requestsToClean.swap(_requests);
         _requests.clear();
         _recentlyCompletedRequestIds.clear();
-        _executor.reset();
     }
     auto opCtxHolder = cc().makeOperationContext();
-    // Ensure that the clean up won't delete any request recovery document (the commands will be
-    // reissued once the scheduler is restarted)
-    _performDeferredCleanup(opCtxHolder.get(), cancelledRequests, false /*includePersistedData*/);
+    _performDeferredCleanup(opCtxHolder.get(), requestsToClean);
 }
 
 
diff --git a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
index 92f9f074441..ba85ee9a6e3 100644
--- a/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
+++ b/src/mongo/db/s/balancer/balancer_commands_scheduler_impl.h
@@ -34,7 +34,6 @@
 #include "mongo/db/s/balancer/type_migration.h"
 #include "mongo/db/s/forwardable_operation_metadata.h"
 #include "mongo/db/service_context.h"
-#include "mongo/executor/scoped_task_executor.h"
 #include "mongo/platform/mutex.h"
 #include "mongo/rpc/get_status_from_command_result.h"
 #include "mongo/s/client/shard.h"
@@ -594,7 +593,7 @@ public:
 private:
     enum class SchedulerState { Recovering, Running, Stopping, Stopped };
 
-    std::unique_ptr<executor::ScopedTaskExecutor> _executor{nullptr};
+    std::shared_ptr<executor::TaskExecutor> _executor{nullptr};
 
     // Protects the in-memory state of the Scheduler
     // (_state, _requests, _unsubmittedRequestIds, _recentlyCompletedRequests).
@@ -648,8 +647,7 @@ private:
      */
     void _performDeferredCleanup(
         OperationContext* opCtx,
-        const stdx::unordered_map<UUID, RequestData, UUID::Hash>& requestsHoldingResources,
-        bool includePersistedData);
+        const stdx::unordered_map<UUID, RequestData, UUID::Hash>& requestsHoldingResources);
 
     CommandSubmissionResult _submit(OperationContext* opCtx,
                                     const CommandSubmissionParameters& data);