Add counters that automatically track object sizes and counts.

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 161 matching lines @@
     }
   }
 
   memset(roots_, 0, sizeof(roots_[0]) * kRootListLength);
   global_contexts_list_ = NULL;
   mark_compact_collector_.heap_ = this;
   external_string_table_.heap_ = this;
   // Put a dummy entry in the remembered pages so we can find the list the
   // minidump even if there are no real unmapped pages.
   RememberUnmappedPage(NULL, false);
+
+  ClearObjectStats(true);
 }
 
 
 intptr_t Heap::Capacity() {
   if (!HasBeenSetUp()) return 0;
 
   return new_space_.Capacity() +
       old_pointer_space_->Capacity() +
       old_data_space_->Capacity() +
       code_space_->Capacity() +
@@ skipping 7026 matching lines @@
     p ^= 0xc1ead & (Page::kPageSize - 1);  // Cleared.
   } else {
     p ^= 0x1d1ed & (Page::kPageSize - 1);  // I died.
   }
   remembered_unmapped_pages_[remembered_unmapped_pages_index_] =
       reinterpret_cast<Address>(p);
   remembered_unmapped_pages_index_++;
   remembered_unmapped_pages_index_ %= kRememberedUnmappedPages;
 }
 
+
+void Heap::ClearObjectStats(bool clear_last_time_stats) {
+  memset(object_counts_, 0, sizeof(object_counts_));
+  memset(object_sizes_, 0, sizeof(object_counts_));

[Michael Starzinger, 2012/07/12 20:12:26]

Better use sizeof(object_sizes_) here.

[danno, 2012/07/12 21:18:16]

Done.

+  if (clear_last_time_stats) {
+    memset(object_counts_last_time_, 0, sizeof(object_counts_last_time_));
+    memset(object_sizes_last_time_, 0, sizeof(object_sizes_last_time_));
+  }
+}
+
+
+void Heap::CheckpointObjectStats() {
+  Counters* counters = isolate()->counters();
+#define ADJUST_LAST_TIME_OBJECT_COUNT(name) \
+  counters->count_of_##name()->Increment(object_counts_[name]); \

[Michael Starzinger, 2012/07/12 20:12:26]

Is there a particular reason we cannot use counter->Set() here? That would
obsolete the last_time_stats tables completely.

[danno, 2012/07/12 21:18:16]

Yes, the reason is that you can have multiple isolates, they all have a heap and
we want the stats to track the usage of all of the isolates. Since there is no
way to track the stats separately per isolate, I have to compute the delta.
Technically, there should be a mutex, which I'll add.
On 2012/07/12 20:12:26, Michael Starzinger wrote:

+  counters->count_of_##name()->Decrement(object_counts_last_time_[name]); \
+  counters->size_of_##name()->Increment(object_sizes_[name]); \
+  counters->size_of_##name()->Decrement(object_sizes_last_time_[name]);
+  INSTANCE_TYPE_LIST(ADJUST_LAST_TIME_OBJECT_COUNT)
+#undef ADJUST_LAST_TIME_OBJECT_COUNT
+  memcpy(object_counts_last_time_, object_counts_,
+         sizeof(object_counts_));
+  memcpy(object_sizes_last_time_, object_sizes_,
+         sizeof(object_sizes_));
+  ClearObjectStats();
+}
+
 } }  // namespace v8::internal