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该类v8::ResourceConstraints定义如下：

class V8EXPORT ResourceConstraints {
 public:
  ResourceConstraints();
  int max_young_space_size() const { return max_young_space_size_; }
  void set_max_young_space_size(int value) { max_young_space_size_ = value; }
  int max_old_space_size() const { return max_old_space_size_; }
  void set_max_old_space_size(int value) { max_old_space_size_ = value; }
  int max_executable_size() { return max_executable_size_; }
  void set_max_executable_size(int value) { max_executable_size_ = value; }
  uint32_t* stack_limit() const { return stack_limit_; }
  // Sets an address beyond which the VM's stack may not grow.
  void set_stack_limit(uint32_t* value) { stack_limit_ = value; }
 private:
  int max_young_space_size_;
  int max_old_space_size_;
  int max_executable_size_;
  uint32_t* stack_limit_;
};

谁能告诉我young_space_size,old_space_size和max_executable_size是什么？它们的单位是什么，它们是如何相关的，等等？似乎没有太多文档。

另外，如何使用该stack_limit物业？例如，如果我希望我的 V8 隔离使用不超过 1MB 的堆栈空间，我将如何计算指针值stack_limit？

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1 回答 1

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v8/test/cctest/test-api.cc 使用这个函数来计算限制：

// Uses the address of a local variable to determine the stack top now.
// Given a size, returns an address that is that far from the current
// top of stack.
static uint32_t* ComputeStackLimit(uint32_t size) {
  uint32_t* answer = &size - (size / sizeof(size));
  // If the size is very large and the stack is very near the bottom of
  // memory then the calculation above may wrap around and give an address
  // that is above the (downwards-growing) stack.  In that case we return
  // a very low address.
  if (answer > &size) return reinterpret_cast<uint32_t*>(sizeof(size));
  return answer;
}
于 2014-01-03T00:44:17.967 回答