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Unformatted text preview: sed. – If the function is cycle based, then use it as the basis for the Ã -best timing function. – If the function is interval based, then we must ﬁnd some method of using the machine’s cycle counters. This may require assembly language coding. ¯ If the anticipated run times of are less than around 0.01 second, then accurate measurements can be performed even on a heavily loaded system, as long as it is uses cycle-based timing. We then proceed in implementing a Ã -best timing function using either gettimeofday or by direct access to the machine’s cycle counter. 9.7 Looking into the Future
There are several features that are being incorporated into systems that will have signiﬁcant impact on performance measurements. ¯ Process-speciﬁc cycle timing. It is relatively easy for the operating system to manage the cycle counter so that it indicates the elapsed number of cycles for a speciﬁc process. All that is required is to store the count as part of the process’ state. Then when the proce...
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- Spring '10
- The American