[R] mcapply not using more than 1 core

[joe meiring]

This does speed up on an OsX install, so something must be wacky with the 
linux install. Any ideas as to what would cause this? 

On Tuesday, August 27, 2013 4:19:31 PM UTC-7, joe meiring wrote:
>
> I can't seem to get mclapply to use more than a single core. I have a 64 
> core server running Linux. 
>
> Fore example: 
>
> library(parallel) 
>
> test <- lapply(1:100,function(x) rnorm(10000)) 
> system.time(x <- lapply(test,function(x) loess.smooth(x,x))) 
> system.time(x <- mclapply(test,function(x) loess.smooth(x,x), 
> mc.cores=32)) 
>
> gives me: 
>
>    user  system elapsed 
>   0.000   0.000   7.441 
>    user  system elapsed 
>   0.000   0.000   8.868 
>
> i.e. mclapply is taking longer than lapply(). What is going wrong here? 
>
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