most efficient way to write data into a file

I want to write 2TB data into one file, in the future it might be a petabyte.

The data is composed of all '1'. For example, 2TB data consisting of "1111111111111......11111" (each byte is represented by '1').

Following is my way:

File.open("data",File::RDWR||File::CREAT) do |file|
  2*1024*1024*1024*1024.times do
  file.write('1')
  end
end

That means, File.write is called 2TB times. From the point of Ruby, is there a better way to implement it?