Second posting since for some reason the first posting apparently didn't make it. -----Original Message----- From: Tom Gardner [mailto:tom94022 at comcast.net] Sent: Monday, June 17, 2013 10:07 AM To: 'cctalk at classiccmp.org' Subject: RE: Early UNIX File Optimization I have a vague recollection that early time sharing systems, in particular UNIX, enforced I/O fairness by fragmenting files and thereby freeing the I/O between fragments. However I don't recall much and this might be an artifact of aging :-) If so, I am curious as to how this was implemented - interleaving sectors or some more complex physical fragmentation or ?? Anyone point me to any references? Tom