[R] more strange behavior of Revolution R 1.3.0

[Uwe Ligges]

Please discuss with REvolution support. Most of us do not have a version 
of REvolution R.

Uwe Ligges



Jason Liao wrote:
> It runs more than twice as slowly using 8 core than using a single core
> in inverting large matrix. Tested on 8 core Windows XP 64 machine. 
> 
>  
> 
>  
> 
>> n = 1000
> 
>> n.simu = 100 
> 
>> func1 = function()
> 
> + {
> 
> +   x = rnorm(n*n)
> 
> +   dim(x)=c(n,n) 
> 
> +  y = solve(x)
> 
> + }
> 
> 
>> setMKLthreads(1)
> 
>> system.time(for(i in 1:n.simu) func1())
> 
>    user  system elapsed 
> 
>   69.48    2.42   71.91 
> 
> 
>> setMKLthreads(8)
> 
>> system.time(for(i in 1:n.simu) func1())
> 
>    user  system elapsed 
> 
>  179.06   17.90   41.70
> 
>  
> 
> Jason Liao
> 
> 
> 	[[alternative HTML version deleted]]
> 
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