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Dhrystone howto

958 bytes added, 16:25, 30 December 2010
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<font style="font-size:110%"><b>4. Run "make"</b></font>
Running make in the current directory should only produce warnings!! Here is an output of the make command with errors warnings relating to c library functions that can be ignored.
<blockquote>
The make command outputs 2 files named '''gcc_dry2''' and '''gcc_dry2reg'''. The author of this version decided to create 2 dhrystone executables . One with register variables, and one without. Either one will work for the benchmark so, feel free to test it out.
1. Run the executable by typing '''./gcc_dry2'''. The program will start to ask you for a ''number of runs''. By convention on newer machines, the number of runs used is about '''~100000000''' (100 million). There are no rules or standards about how many runs it should be, what matters is the consistency of the result. For consistent results, dhrystone is executed more than 5 times with same values for number of runs.
== Project Leader(s) ==
Name<font style="font-size:110%><b>1. Run the executable by typing ''./gcc_dry2''</b></font> The program will start to ask you for a ''number of runs''. By convention on newer machines (s>=1GHz) , the number of primary runs used is about '''~100000000''' (100 million). There are no rules or standards about how many runs it should be. Some people working calculate the number of runs through "Dhrystone run time erros" (way too advanced); what matters is the consistency of the result. For consistent results, dhrystone is executed more than 5 times with same values for number of runs.  <font style="font-size:110%><b>2. Calculate for DMIPS</b></font> One common representation of the Dhrystone benchmark is DMIPS. DMIPS (Dhrystone MIPS ). It is obtained when the Dhrystone score is divided by '''1757''' (the number of Dhrystones per second obtained on the projectVAX 11/780, nominally a 1 MIPS machine). Given the result: <blockquote><code>Microseconds for one run through Dhrystone: 0.8<br />Dhrystones per Second: 1333333.4</code></blockquote>  Using the formula: '''1333333. 4 / 1757 = If you want to join 758.87''' ''DMIPS''  The result shown was an actual test for a project as leader, discuss beagleboardXM machine with other leaders 1GHz of processor speed. = And... = <font style="font-size:90%">From ARM White paper</font><br /> "When firstreleased, the Dhrystone benchmark fulfilled a useful function – at least it gave an alternative indicator to vendors’ literal MIPS ratings. However, more than twenty years later, there are undoubtedly better benchmarks available for measuring processor performance. Include links to personal pages within wiki"
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