SERVER-27725 Do not perform orphan check while doing range deletion as part of chunk receive

3 files changed, 19 insertions, 18 deletions

diff --git a/src/mongo/db/s/metadata_manager.cpp b/src/mongo/db/s/metadata_manager.cpp
index 0bba1ff478e..afda09358f2 100644
--- a/src/mongo/db/s/metadata_manager.cpp
+++ b/src/mongo/db/s/metadata_manager.cpp
@@ -192,8 +192,6 @@ void MetadataManager::beginReceive(const ChunkRange& range) {
         auto itRecv = _receivingChunks.find(overlapChunkMin.first);
         invariant(itRecv != _receivingChunks.end());
 
-        const ChunkRange receivingRange(itRecv->first, itRecv->second.getMaxKey());
-
         _receivingChunks.erase(itRecv);
     }
 
diff --git a/src/mongo/db/s/migration_destination_manager.cpp b/src/mongo/db/s/migration_destination_manager.cpp
index 8dae501c57e..72284059c07 100644
--- a/src/mongo/db/s/migration_destination_manager.cpp
+++ b/src/mongo/db/s/migration_destination_manager.cpp
@@ -665,6 +665,12 @@ void MigrationDestinationManager::_migrateDriver(OperationContext* txn,
             wunit.commit();
         }
 
+        Status status = _notePending(txn, _nss, min, max, epoch);
+        if (!status.isOK()) {
+            setState(FAIL);
+            return;
+        }
+
         timing.done(1);
         MONGO_FAIL_POINT_PAUSE_WHILE_SET(migrateThreadHangAtStep1);
     }
@@ -680,7 +686,12 @@ void MigrationDestinationManager::_migrateDriver(OperationContext* txn,
         // results
         deleterOptions.waitForOpenCursors = false;
         deleterOptions.fromMigrate = true;
-        deleterOptions.onlyRemoveOrphanedDocs = true;
+
+        // There is no need to perform checking for orphaned docs as part of the range deletion,
+        // because the call above (to _notePending) will ensure that the chunk which is coming in is
+        // not currently owned by this shard and the scopedRegisterReceiveChunk would prevent this
+        // chunk from getting received while range deletion is running.
+        deleterOptions.onlyRemoveOrphanedDocs = false;
         deleterOptions.removeSaverReason = "preCleanup";
 
         if (!getDeleter()->deleteNow(txn, deleterOptions, &errmsg)) {
@@ -689,12 +700,6 @@ void MigrationDestinationManager::_migrateDriver(OperationContext* txn,
             return;
         }
 
-        Status status = _notePending(txn, _nss, min, max, epoch);
-        if (!status.isOK()) {
-            setState(FAIL);
-            return;
-        }
-
         timing.done(2);
         MONGO_FAIL_POINT_PAUSE_WHILE_SET(migrateThreadHangAtStep2);
     }
diff --git a/src/mongo/db/s/migration_destination_manager_legacy_commands.cpp b/src/mongo/db/s/migration_destination_manager_legacy_commands.cpp
index ac9752fd96d..4c28de35b44 100644
--- a/src/mongo/db/s/migration_destination_manager_legacy_commands.cpp
+++ b/src/mongo/db/s/migration_destination_manager_legacy_commands.cpp
@@ -111,11 +111,16 @@ public:
             }
         }
 
-
         const NamespaceString nss(cmdObj.firstElement().String());
-
         const auto chunkRange = uassertStatusOK(ChunkRange::fromBSON(cmdObj));
 
+        const MigrationSessionId migrationSessionId(
+            uassertStatusOK(MigrationSessionId::extractFromBSON(cmdObj)));
+
+        // Ensure this shard is not currently receiving or donating any chunks.
+        auto scopedRegisterReceiveChunk(
+            uassertStatusOK(shardingState->registerReceiveChunk(nss, chunkRange, fromShard)));
+
         // Refresh our collection manager from the config server, we need a collection manager to
         // start registering pending chunks. We force the remote refresh here to make the behavior
         // consistent and predictable, generally we'd refresh anyway, and to be paranoid.
@@ -147,13 +152,6 @@ public:
             return false;
         }
 
-        const MigrationSessionId migrationSessionId(
-            uassertStatusOK(MigrationSessionId::extractFromBSON(cmdObj)));
-
-        // Ensure this shard is not currently receiving or donating any chunks.
-        auto scopedRegisterReceiveChunk(
-            uassertStatusOK(shardingState->registerReceiveChunk(nss, chunkRange, fromShard)));
-
         // Even if this shard is not currently donating any chunks, it may still have pending
         // deletes from a previous migration, particularly if there are still open cursors on the
         // range pending deletion.