Track per-class promotion stats.

runtime/vm/class_table.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_CLASS_TABLE_H_
 #define VM_CLASS_TABLE_H_
 
 #include "platform/assert.h"
 #include "vm/globals.h"
 
@@ skipping 56 matching lines @@
   // Snapshot before GC.
   AllocStats<intptr_t> pre_gc;
   // Live after GC.
   AllocStats<intptr_t> post_gc;
   // Allocations since the last GC.
   AllocStats<intptr_t> recent;
   // Accumulated (across GC) allocations .
   AllocStats<int64_t> accumulated;
   // Snapshot of recent at the time of the last reset.
   AllocStats<intptr_t> last_reset;
+  // Promoted from new to old by last new GC.
+  intptr_t promoted_count;
+  intptr_t promoted_size;

[Cutch, 2014/08/20 17:46:57]

Is this accumulated over all GCs or just the last GC? If they are accumulated
you should probably using an int64_t.

[koda, 2014/08/20 17:49:27]

Just the last (as the comment above states).

 
   static intptr_t allocated_since_gc_new_space_offset() {
     return OFFSET_OF(ClassHeapStats, recent) +
            OFFSET_OF(AllocStats<intptr_t>, new_count);
   }
   static intptr_t allocated_since_gc_old_space_offset() {
     return OFFSET_OF(ClassHeapStats, recent) +
            OFFSET_OF(AllocStats<intptr_t>, old_count);
   }
   static intptr_t allocated_size_since_gc_new_space_offset() {
     return OFFSET_OF(ClassHeapStats, recent) +
            OFFSET_OF(AllocStats<intptr_t>, new_size);
   }
   static intptr_t allocated_size_since_gc_old_space_offset() {
     return OFFSET_OF(ClassHeapStats, recent) +
            OFFSET_OF(AllocStats<intptr_t>, old_size);
   }
 
   void Initialize();
   void ResetAtNewGC();
   void ResetAtOldGC();
   void ResetAccumulator();
+  void UpdatePromotedAfterNewGC();
   void UpdateSize(intptr_t instance_size);
   void PrintToJSONObject(const Class& cls, JSONObject* obj) const;
+
+ private:
+  // Recent old at start of last new GC (used to compute promoted_*).
+  intptr_t old_pre_new_gc_count_;
+  intptr_t old_pre_new_gc_size_;
 };
 
 
 class ClassTable {
  public:
   ClassTable();
   ~ClassTable();
 
   RawClass* At(intptr_t index) const {
     ASSERT(IsValidIndex(index));
@@ skipping 28 matching lines @@
   }
 
   // Called whenever a class is allocated in the runtime.
   void UpdateAllocatedNew(intptr_t cid, intptr_t size);
   void UpdateAllocatedOld(intptr_t cid, intptr_t size);
 
   // Called whenever a old GC occurs.
   void ResetCountersOld();
   // Called whenever a new GC occurs.
   void ResetCountersNew();
+  // Called immediately after a new GC.
+  void UpdatePromoted();
 
   // Used by the generated code.
   uword PredefinedClassHeapStatsTableAddress() {
     return reinterpret_cast<uword>(predefined_class_heap_stats_table_);
   }
 
   // Used by generated code.
   uword ClassStatsTableAddress() {
     return reinterpret_cast<uword>(&class_heap_stats_table_);
   }
@@ skipping 24 matching lines @@
   ClassHeapStats* PreliminaryStatsAt(intptr_t cid);
   void UpdateLiveOld(intptr_t cid, intptr_t size);
   void UpdateLiveNew(intptr_t cid, intptr_t size);
 
   DISALLOW_COPY_AND_ASSIGN(ClassTable);
 };
 
 }  // namespace dart
 
 #endif  // VM_CLASS_TABLE_H_