Agree whole heartedly. I was asking this thinking of open(<file>,O_DIRECT|O_RDONLY); that bypasses buffer cache and read directly from the disk that atleast so

Agree whole heartedly. I was asking this thinking of open(<file>,O_DIRECT|O_RDONLY); that bypasses buffer cache and read directly from the disk that atleast solves buffer cache i guess. The disk cache is another thing ie if we disable it we are good at the cost of performance. I was pointing that tests can do these kind of things.