A Unix Performance Monitor
Richard Montagu Maurice · UC Research Repository (University of Canterbury) · 1987
The aim of this project was to produce a Unix implementation of the Penny and Ashton[Penny86, 87] performance monitor model, a model which attempts to provide insight into the causes of user response time delays. An implementation of the model had earlier been produced for the Primos operating system[Ashton84], an operating system with a single process per interactive user, but not for an operating system like Unix where interactive users are supported by multiple processes. Performance monitoring, the Penny and Ashton model, and the adaptation of the model for a Unix system are the subjects of sections 2 and 3. Sections 4 and 5 examine the design and implementation of the actual Unix monitor, called MON for convenience, and some results produced by MON are given in section 6. Section 7 considers the veracity of results produced by MON: the validity of techniques used in MON to establish the state of the system at sample time, and the degree to which MON interferes with that state. Additions to be made to MON are discussed in section 8 and the report concludes in section 9 with an examination of MON as it is at present.