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→About Dhrystone
Both Whetstone and Dhrystone are synthetic benchmarks, meaning that they are simple programs that are carefully designed to statistically mimic the processor usage of some common set of programs. Whetstone, developed in 1972, originally strove to mimic typical Algol 60 programs based on measurements from 1970, but eventually became most popular in its Fortran version, reflecting the highly numerical orientation of computing in the 1960s.
<font style="font-size:120110%"><b>Advantages of Using Dhrystone:Fundamentals</b></font>---<font style="font-size:90%">From ARM White Paper</font>Dhrystone has a number of attributes that have led to it being widely used in the past as ameasure of CPU performance.Foremost, Dhrystone is compact, widely available in the public domain, and simple torun. Significantly, there are no lengthy certification processes to go through before citingDhrystone figures.Dhrystone compares the performance of the processor under benchmark to that of areference machine. This is an advantage over quoting ‘straight’ MIPS numbers sinceusing a reference machine effectively compensates for differences in the richness ofcompeting instruction sets. For example, literal comparison of the ‘millions ofinstructions per second’ numbers for a RISC architecture and a CISC architecture is notmeaningful. The industry has adopted the VAX 11/780 as the reference 1 MIP machine. The VAX11/780 achieves 1757 Dhrystones per second. The Dhrystone figure is calculated bymeasuring the number of Dhrystones per second for the system, and dividing that by1757. So "80 MIPS" means "80 Dhrystone VAX MIPS", which means 80 times fasterthan a VAX 11/780. A DMIPS/MHz rating takes this normalization process one stepfurther, enabling comparison of processor performance at different clock rates.For all of these reasons, in the past, Dhrystone has been a widely quoted benchmarkfigure. In theory, Dhrystone should provide a basis for the comparison of processorperformances.However, some of the apparent advantages of Dhrystone are also significant weaknessesof the benchmark. Dhrystone numbers actually reflect the performance of the C compilerand libraries, probably more so than the performance of the processor itself. Also, lack ofindependent certification means that customers are dependent on processor vendors toquote accurate and meaningful Dhrystone data.
== Project Description ==