Reduce boot-up memory use of V8.

src/snapshot.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
 // met:
 //
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 #include "isolate.h"
+#include "spaces.h"
 
 #ifndef V8_SNAPSHOT_H_
 #define V8_SNAPSHOT_H_
 
 namespace v8 {
 namespace internal {
 
 class Snapshot {
  public:
   // Initialize the VM from the given snapshot file. If snapshot_file is
@@ skipping 40 matching lines @@
   static const int size_;
   static const int raw_size_;
   static const int context_size_;
   static const int context_raw_size_;
 
   static bool Deserialize(const byte* content, int len);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Snapshot);
 };
 
+
+// These are the sizes of the spaces that are needed in order to unpack the
+// VM boot snapshot.
+const int kMinimumSpaceSizes[LAST_SPACE + 1] = {
+  0,           // New space.
+  512 * 1024,  // Old pointer space.
+  128 * 1024,  // Old data space.
+  256 * 1024,  // Code space.
+  64 * 1024,   // Map space.
+  64 * 1024,   // Cell space.
+  0            // Large object space.
+};
+
+
+
 } }  // namespace v8::internal
 
 #endif  // V8_SNAPSHOT_H_