Effects of scheduling on file memory operations

File system activity is a prime factor affecting the throughput of any computing system, for the file memory is, in a very real sense, the heart of the system. No program can ever be executed without such secondary storage. It is here that input files are stored, that files resulting as the output of processes are written, that "scratchwork" required by operating processes may be placed. In a multiprogrammed computing system, there is a considerable burden on secondary storage, resulting both from constant traffic in and out of main memory (core memory), and from the large number of permanent files that may be in residence. It is clear that the demand placed on the file memory system is extraordinarily heavy; and it is essential that every part of the computing system interacting with file memory do so smoothly and efficiently.