SERVER-52629 Apply lookup by ShardId first in non config shards

1 files changed, 7 insertions, 5 deletions

diff --git a/src/mongo/s/client/shard_registry.cpp b/src/mongo/s/client/shard_registry.cpp
index 28b4af8dc3c..3d5f8bc3e8d 100644
--- a/src/mongo/s/client/shard_registry.cpp
+++ b/src/mongo/s/client/shard_registry.cpp
@@ -328,7 +328,13 @@ std::shared_ptr<Shard> ShardRegistry::getConfigShard() const {
 
 StatusWith<std::shared_ptr<Shard>> ShardRegistry::getShard(OperationContext* opCtx,
                                                            const ShardId& shardId) {
-    // First check if this is a config shard lookup.
+    // First check if this is a non config shard lookup
+    // This call will may be blocking if there is an ongoing or a need of a cache rebuild
+    if (auto shard = _getData(opCtx)->findShard(shardId)) {
+        return shard;
+    }
+
+    // then check if this is a config shard (this call is blocking in any case)
     {
         stdx::lock_guard<Latch> lk(_mutex);
         if (auto shard = _configShardData.findShard(shardId)) {
@@ -336,10 +342,6 @@ StatusWith<std::shared_ptr<Shard>> ShardRegistry::getShard(OperationContext* opC
         }
     }
 
-    if (auto shard = _getData(opCtx)->findShard(shardId)) {
-        return shard;
-    }
-
     // Reload and try again if the shard was not in the registry
     reload(opCtx);
     if (auto shard = _getData(opCtx)->findShard(shardId)) {