diff --git a/update_metadata.proto b/update_metadata.proto
index 84b991b..96e04f2 100644
--- a/update_metadata.proto
+++ b/update_metadata.proto
@@ -331,6 +331,11 @@
   repeated string partition_names = 3;
 }
 
+message VABCFeatureSet {
+  optional bool threaded = 1;
+  optional bool batch_writes = 2;
+}
+
 // Metadata related to all dynamic partitions.
 message DynamicPartitionMetadata {
   // All updatable groups present in |partitions| of this DeltaArchiveManifest.
@@ -361,6 +366,9 @@
   // COW version used by VABC. The represents the major version in the COW
   // header
   optional uint32 cow_version = 5;
+
+  // A collection of knobs to tune Virtual AB Compression
+  optional VABCFeatureSet vabc_feature_set = 6;
 }
 
 // Definition has been duplicated from