Virtual memory variable dereference a pointer or make

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Unformatted text preview: 1 0 10 20 30 40 50 Expected CPU Time (ms) Figure 9.16: Measurements with Compensation for Timer Interrupt Overhead This approach greatly improves the accuracy of longer duration measurements on a lightly loaded machine. 1. We must determine how much time is required to handle a single timer interrupt. To preserve the property that we never underestimate the execution time of the procedure, we should determine the minimum number of clock cycles required to service a timer interrupt. That way we will never overcompensate. 2. We must determine how many timer interrupts occur during the period we are measuring. Using a method similar to that used to generate the traces shown in Figures 9.3 and 9.5, we can detect periods of inactivity and determine their duration. Some of these will be due to timer interrupts, and some will be due to other system events. We can determine whether a timer interrupt has occurred by using the times procedure, since the value it returns will be increase one tick each time a timer interrupt occurs. We conducted...
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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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