Double default new gen size on 64-bit (like old gen).

runtime/vm/dart.cc

 // Copyright (c) 2013, 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.
 
 #include "vm/dart.h"
 
 #include "vm/code_observers.h"
 #include "vm/cpu.h"
 #include "vm/dart_api_state.h"
 #include "vm/dart_entry.h"
@@ skipping 12 matching lines @@
 #include "vm/snapshot.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 #include "vm/thread_interrupter.h"
 #include "vm/thread_pool.h"
 #include "vm/virtual_memory.h"
 #include "vm/zone.h"
 
 namespace dart {
 
-DEFINE_FLAG(int, new_gen_heap_size, 32, "new gen heap size in MB,"
+DEFINE_FLAG(int, new_gen_heap_size, 8 << kWordSizeLog2,
+            "new gen heap size in MB,"
             "e.g: --new_gen_heap_size=64 allocates a 64MB new gen heap");
 DEFINE_FLAG(int, old_gen_heap_size, Heap::kHeapSizeInMB,
             "old gen heap size in MB,"
             "e.g: --old_gen_heap_size=1024 allocates a 1024MB old gen heap");
 
 DECLARE_FLAG(bool, print_class_table);
 DECLARE_FLAG(bool, trace_isolates);
 
 Isolate* Dart::vm_isolate_ = NULL;
 ThreadPool* Dart::thread_pool_ = NULL;
@@ skipping 256 matching lines @@
   return predefined_handles_->handles_.AllocateScopedHandle();
 }
 
 
 bool Dart::IsReadOnlyHandle(uword address) {
   ASSERT(predefined_handles_ != NULL);
   return predefined_handles_->handles_.IsValidScopedHandle(address);
 }
 
 }  // namespace dart