This is not entirely true in R: Details:
‘proc.time’ returns five elements for backwards compatibility, but its ‘print’ method prints a named vector of length 3. The first two entries are the total user and system CPU times of the current R process and any child processes on which it has waited, and the third entry is the ‘real’ elapsed time since the process was started. On Wednesday, July 6, 2016 at 5:11:04 PM UTC+2, Michael Borregaard wrote: > > I am not seeing your speed-up in R? elapsed is less time, but user > significantly more, and it is the sum that counts. > When executing in parallel the language needs to copy the data to the > workers. If the matrices are large, that takes longer than the speedup of > the parallel execution. See what happens with a smaller matrix and then > repeating the operation on the workers. > >