1810	 Is Automatic Folding of Programs Efficient Enough To Displace Manual	 The operation of folding a program into the available memory is discussed. Measurements by Brown et al. and by Nelson on an automatic folding mechanism of simple design a demand paging unit built at the IBM Research Center by Belady Nelson O Neil and others permitting its quality to be compared with that of manual folding are discussed and it is shown that given some care in use the unit performs satisfactorily under the conditions tested even though it is operating across a memory-to-storage interface with a very large speed difference. The disadvantages of prefolding which is required when the folding is manual are examined and a number of the important troubles which beset computing today are shown to arise from or be aggravated by this source. It is concluded that a folding mechanism will probably become a normal part of most computing systems. paging automatic paging demand paging folding automatic folding storage hierarchies memory hierarchies replacement algorithms performance measurement
