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digitalmars.D - Dhrystone Benchmark

reply Tower Ty <towerty msn.com.au> writes:
I ran the above programs in D on my machine and got wildly varying results as
soDhrystone Benchmark, Version 2.1 (Language: D)
Register option not selected.
Microseconds for one loop:     1.8
Dhrystones per second:   552669.4
VAX MIPS rating:    314.553

Dhrystone Benchmark, Version 2.1 (Language: D)
Register option not selected.
Microseconds for one loop:     0.3
Dhrystones per second:  3333333.3
VAX MIPS rating:   1897.173


It settled on 
Register option selected?  NO
Microseconds for one run through Dhrystone:     0.3
Dhrystones per Second:                       3333333.3
VAX MIPS rating =   1897.173


My question is why the massive variation  and why does the benchmark take the
highest ?
Mar 19 2008
parent renoX <renosky free.fr> writes:
Tower Ty a écrit :
[cut]
 My question is why the massive variation  and why does the benchmark take the
highest ?

Well I don't know this particular benchmark so that's just a guess but maybe the variation is caused by the scheduler or by the GC. Maybe it's possible to disable the GC to see if the variation is reduced? As for taking the highest figure: if the variation is caused by process scheduling then it make sense to show the best performance as the result of the benchmark if you're trying to measure the runtime performance of your binary not the scheduler's performance.. Regards, renoX
Mar 19 2008