YT-27970: Multiplexing for RPC requests

* Changelog entry
  Type: fix
  Component: cpp-sdk

Mark light and heavy RPC requests with different multiplexing bands. Only for PingTransaction for now
commit_hash:9177c1e3811a5108933a87dd3f241d235490ce2d

2 files changed, 8 insertions, 0 deletions

diff --git a/yt/cpp/mapreduce/interface/config.cpp b/yt/cpp/mapreduce/interface/config.cpp
index 8399ed042c1..e222e35c723 100644
--- a/yt/cpp/mapreduce/interface/config.cpp
+++ b/yt/cpp/mapreduce/interface/config.cpp
@@ -477,6 +477,7 @@ void Serialize(const TConfig& config, NYson::IYsonConsumer* consumer)
         .Item("enable_debug_command_line_arguments").Value(config.EnableDebugCommandLineArguments)
         .Item("config_remote_patch_path").Value(config.ConfigRemotePatchPath)
         .Item("enable_client_tracing").Value(config.EnableClientTracing)
+        .Item("enable_multiplexing_band").Value(config.EnableControlMultiplexingBand)
     .EndMap();
 }
 
@@ -549,6 +550,7 @@ void Deserialize(TConfig& config, const TNode& node)
     DESERIALIZE_ITEM("enable_debug_command_line_arguments", config.EnableDebugCommandLineArguments);
     DESERIALIZE_ITEM("config_remote_patch_path", config.ConfigRemotePatchPath);
     DESERIALIZE_ITEM("enable_client_tracing", config.EnableClientTracing);
+    DESERIALIZE_ITEM("enable_multiplexing_band", config.EnableControlMultiplexingBand);
 }
 
 #undef DESERIALIZE_ITEM
diff --git a/yt/cpp/mapreduce/interface/config.h b/yt/cpp/mapreduce/interface/config.h
index a2c3f9fdde8..03c0cd53fee 100644
--- a/yt/cpp/mapreduce/interface/config.h
+++ b/yt/cpp/mapreduce/interface/config.h
@@ -294,6 +294,12 @@ struct TConfig
     /// Allow to create trace_id on client side and propogate with request
     bool EnableClientTracing = true;
 
+    /// Use a separate connection for lightweight control requests.
+    /// If this option is set to true, a separate connection is opened for lightweight requests (for example, ping_transaction).
+    /// This is needed so that important lightweight requests do not wait for heavy requests, such as file writes, to complete.
+    /// However, using this option increases the number of open TCP connections.
+    bool EnableControlMultiplexingBand = false;
+
     static bool GetBool(const char* var, bool defaultValue = false);
     static int GetInt(const char* var, int defaultValue);
     static TDuration GetDuration(const char* var, TDuration defaultValue);