Read Extremely large file efficiently in C#

ReadGigaDataFile.cs

using (FileStream fs = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
using (BufferedStream bs = new BufferedStream(fs))
using (StreamReader sr = new StreamReader(bs))
{
    string line;
    while ((line = sr.ReadLine()) != null)
    {

    }
}