End aside 104 vm as a tool for memory management in

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Unformatted text preview: the cache before each measurement. These parameters can be set by functions that are also in the library. See the file fcyc.h for details. 9.9 Summary We have seen that computer systems have two fundamentally different methods of recording the passage of time. Timer interrupts occur at a rate that seems very fast when viewed on a macroscopic scale but very slow when viewed on a microscopic scale. By counting intervals, the system can get a very rough measure of program execution time. This method is only useful for long-duration measurements. Cycle counters are very fast, giving good measurements on a microscopic scale. For cycle counters that measure absolute time, the effects of context switching can induce error ranging from small (on a lightly loaded system) to very large (on a heavily loaded system). Thus, no scheme is ideal. It is important to understand the accuracy achievable on a particular system. Through this effort to devise an accurate timing scheme and to evaluate its performance on a number...
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This note was uploaded on 09/02/2010 for the course ELECTRICAL 360 taught by Professor Schultz during the Spring '10 term at BYU.

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