Reduce boot-up memory use of V8.

src/d8.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 108 matching lines @@
 i::Mutex* Shell::context_mutex_(i::OS::CreateMutex());
 Persistent<Context> Shell::utility_context_;
 LineEditor* Shell::console = NULL;
 #endif  // V8_SHARED
 
 Persistent<Context> Shell::evaluation_context_;
 ShellOptions Shell::options;
 const char* Shell::kPrompt = "d8> ";
 
 
+const int MB = 1024 * 1024;
+
+
 #ifndef V8_SHARED
 bool CounterMap::Match(void* key1, void* key2) {
   const char* name1 = reinterpret_cast<const char*>(key1);
   const char* name2 = reinterpret_cast<const char*>(key2);
   return strcmp(name1, name2) == 0;
 }
 #endif  // V8_SHARED
 
 
 // Converts a V8 value to a C string.
@@ skipping 1045 matching lines @@
   const char* chars = ReadChars(name, &size);
   if (chars == NULL) return Handle<String>();
   Handle<String> result = String::New(chars, size);
   delete[] chars;
   return result;
 }
 
 
 #ifndef V8_SHARED
 i::Thread::Options SourceGroup::GetThreadOptions() {
-  i::Thread::Options options;
-  options.name = "IsolateThread";
   // On some systems (OSX 10.6) the stack size default is 0.5Mb or less
   // which is not enough to parse the big literal expressions used in tests.
   // The stack size should be at least StackGuard::kLimitSize + some
-  // OS-specific padding for thread startup code.
-  options.stack_size = 2 << 20;  // 2 Mb seems to be enough
-  return options;
+  // OS-specific padding for thread startup code.  2Mbytes seems to be enough.
+  return i::Thread::Options("IsolateThread", 2 * MB);
 }
 
 
 void SourceGroup::ExecuteInThread() {
   Isolate* isolate = Isolate::New();
   do {
     if (next_semaphore_ != NULL) next_semaphore_->Wait();
     {
       Isolate::Scope iscope(isolate);
       Locker lock(isolate);
@@ skipping 292 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif