SERVER-29489 Use 'maxTimeMs' when calling listDatabases against shards

2 files changed, 8 insertions, 1 deletions

diff --git a/src/mongo/s/catalog/sharding_catalog_test.cpp b/src/mongo/s/catalog/sharding_catalog_test.cpp
index 54ec129b13c..0e0085e8c30 100644
--- a/src/mongo/s/catalog/sharding_catalog_test.cpp
+++ b/src/mongo/s/catalog/sharding_catalog_test.cpp
@@ -1786,7 +1786,7 @@ TEST_F(ShardingCatalogClientTest, EnableShardingNoDBExists) {
     onCommand([](const RemoteCommandRequest& request) {
         ASSERT_EQ(HostAndPort("shard0:12"), request.target);
         ASSERT_EQ("admin", request.dbname);
-        ASSERT_BSONOBJ_EQ(BSON("listDatabases" << 1), request.cmdObj);
+        ASSERT_BSONOBJ_EQ(BSON("listDatabases" << 1 << "maxTimeMS" << 600000), request.cmdObj);
 
         ASSERT_BSONOBJ_EQ(ReadPreferenceSetting::secondaryPreferredMetadata(),
                           rpc::TrackingMetadata::removeTrackingData(request.metadata));
diff --git a/src/mongo/s/shard_util.cpp b/src/mongo/s/shard_util.cpp
index b440a6c6491..b66cfc82ce9 100644
--- a/src/mongo/s/shard_util.cpp
+++ b/src/mongo/s/shard_util.cpp
@@ -59,15 +59,22 @@ StatusWith<long long> retrieveTotalShardSize(OperationContext* opCtx, const Shar
         return shardStatus.getStatus();
     }
 
+    // Since 'listDatabases' is potentially slow in the presence of large number of collections, use
+    // a higher maxTimeMS to prevent it from prematurely timing out
+    const Minutes maxTimeMSOverride{10};
+
     auto listDatabasesStatus = shardStatus.getValue()->runCommandWithFixedRetryAttempts(
         opCtx,
         ReadPreferenceSetting{ReadPreference::PrimaryPreferred},
         "admin",
         BSON("listDatabases" << 1),
+        maxTimeMSOverride,
         Shard::RetryPolicy::kIdempotent);
+
     if (!listDatabasesStatus.isOK()) {
         return std::move(listDatabasesStatus.getStatus());
     }
+
     if (!listDatabasesStatus.getValue().commandStatus.isOK()) {
         return std::move(listDatabasesStatus.getValue().commandStatus);
     }