Print promotion rate and semi-space copy rate in --trace-gc-nvp.

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 5d338b2122374a163e083aca1453c7c135bc4c0b..d6503cf7b7c62bbbd055bf502c512608db993cf2 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -2056,7 +2056,9 @@ class ScavengingVisitor : public StaticVisitorBase {
           }
         }
 
-        heap->tracer()->increment_promoted_objects_size(object_size);
+        if (FLAG_trace_gc) {

[Michael Starzinger, 2014/05/16 11:30:37]

nit: This makes the code harder to read and I am not sure if it actually has
significant profit. Would you be willing to go back to increment unconditionally
here?

[Hannes Payer (out of office), 2014/05/20 09:29:14]

Done.

+          heap->tracer()->increment_promoted_objects_size(object_size);
+        }
         return;
       }
     }
@@ -2075,6 +2077,9 @@ class ScavengingVisitor : public StaticVisitorBase {
     // buffer.
     *slot = target;
     MigrateObject(heap, object, target, object_size);
+    if (FLAG_trace_gc) {

[Michael Starzinger, 2014/05/16 11:30:37]

nit: Likewise.

[Hannes Payer (out of office), 2014/05/20 09:29:14]

Done.

+      heap->tracer()->increment_semi_space_copied_object_size(object_size);
+    }
     return;
   }
 
@@ -6029,6 +6034,7 @@ GCTracer::GCTracer(Heap* heap,
       allocated_since_last_gc_(0),
       spent_in_mutator_(0),
       promoted_objects_size_(0),
+      semi_space_copied_object_size_(0),
       nodes_died_in_new_space_(0),
       nodes_copied_in_new_space_(0),
       nodes_promoted_(0),
@@ -6176,10 +6182,18 @@ GCTracer::~GCTracer() {
 
     PrintF("allocated=%" V8_PTR_PREFIX "d ", allocated_since_last_gc_);
     PrintF("promoted=%" V8_PTR_PREFIX "d ", promoted_objects_size_);
+    PrintF("semi_space_copied=%" V8_PTR_PREFIX "d ",
+        semi_space_copied_object_size_);
     PrintF("nodes_died_in_new=%d ", nodes_died_in_new_space_);
     PrintF("nodes_copied_in_new=%d ", nodes_copied_in_new_space_);
     PrintF("nodes_promoted=%d ", nodes_promoted_);
-    PrintF("survived=%.1f%% ", heap_->survival_rate_);
+    PrintF("survival_rate=%.1f%% ", heap_->survival_rate_);
+    PrintF("promotion_rate=%.1f%% ",
+        (static_cast<double>(promoted_objects_size_) /
+            static_cast<double>(heap_->new_space()->Capacity())) * 100);
+    PrintF("semi_space_copy_rate=%.1f%% ",
+        (static_cast<double>(semi_space_copied_object_size_) /
+            static_cast<double>(heap_->new_space()->Capacity())) * 100);
 
     if (collector_ == SCAVENGER) {
       PrintF("stepscount=%d ", steps_count_since_last_gc_);