If I try to create a binary io.BufferedReader with a 1GB buffer, either with open(foo, "rb", buffering=1024*1024*1024) or with BufferedReader(open(foo, "rb"), buffer_size=1024*1024*1024) and then I read some data from a 4GB file, why does Python's memory usage not go up immediately by 1GB? Is there a much smaller maximum buffer size? Does it not pre-load data to fill the buffer if I only request a few bytes or kilobytes at a time? Am I doing something wrong? -- https://mail.python.org/mailman/listinfo/python-list
