diff --git a/cmds/statsd/src/atoms.proto b/cmds/statsd/src/atoms.proto
index 23a4437..f215d77 100644
--- a/cmds/statsd/src/atoms.proto
+++ b/cmds/statsd/src/atoms.proto
@@ -8204,14 +8204,6 @@
 }
 
 /**
- * HWUI renders pipeline type: GL (0) or Vulkan (1).
- */
-enum PipelineType {
-    GL = 0;
-    VULKAN = 1;
-}
-
-/**
  * HWUI stats for a given app.
  */
 message GraphicsStats {
@@ -8224,9 +8216,16 @@
     // The start & end timestamps in UTC as
     // milliseconds since January 1, 1970
     // Compatible with java.util.Date#setTime()
-    optional int64 stats_start = 3;
+    optional int64 start_millis = 3;
 
-    optional int64 stats_end = 4;
+    optional int64 end_millis = 4;
+
+    // HWUI renders pipeline type: GL (1) or Vulkan (2).
+    enum PipelineType {
+        UNKNOWN = 0;
+        GL = 1;
+        VULKAN = 2;
+    }
 
     // HWUI renders pipeline type: GL or Vulkan.
     optional PipelineType pipeline = 5;
diff --git a/core/proto/android/service/graphicsstats.proto b/core/proto/android/service/graphicsstats.proto
index 2de5b7f..bb654f0 100644
--- a/core/proto/android/service/graphicsstats.proto
+++ b/core/proto/android/service/graphicsstats.proto
@@ -33,8 +33,9 @@
 
 message GraphicsStatsProto {
     enum PipelineType {
-        GL = 0;
-        VULKAN = 1;
+        UNKNOWN = 0;
+        GL = 1;
+        VULKAN = 2;
     }
     option (android.msg_privacy).dest = DEST_AUTOMATIC;
 
diff --git a/libs/hwui/protos/graphicsstats.proto b/libs/hwui/protos/graphicsstats.proto
index dd5676c..745393c 100644
--- a/libs/hwui/protos/graphicsstats.proto
+++ b/libs/hwui/protos/graphicsstats.proto
@@ -30,8 +30,9 @@
 
 message GraphicsStatsProto {
     enum PipelineType {
-        GL = 0;
-        VULKAN = 1;
+        UNKNOWN = 0;
+        GL = 1;
+        VULKAN = 2;
     }
 
     // The package name of the app