# thread_testing_matrixinverse_noMKL.txt
#
# Tests matrix inversion using the 'parallelMatrixInv' function.
#
# Stock R 3.3.1 (x64) is used with the standard BLAS library. 
# The number of RcppParallel threads is varied from 1 to 6 (the number of physical cores in 
# the machine).
# The matrix inversion is repeated five times for each setting.


> print(RcppThreads)
[1] 1
> times
[[1]]
   user  system elapsed 
   4.13    0.15    4.28 

[[2]]
   user  system elapsed 
   4.04    0.17    4.21 

[[3]]
   user  system elapsed 
   4.01    0.09    4.12 

[[4]]
   user  system elapsed 
   4.07    0.06    4.15 

[[5]]
   user  system elapsed 
   4.11    0.12    4.26 

> 
> 
> 
> 
> RcppThreads <- 2
> RcppParallel::setThreadOptions(numThreads = RcppThreads)
> times <- list()
> for (i in 1:5){
+   times[[i]] <- 
+     system.time(parallelMatrixInv(x))
+ }
> print(RcppThreads)
[1] 2
> times
[[1]]
   user  system elapsed 
   4.11    0.13    2.25 

[[2]]
   user  system elapsed 
   4.02    0.18    2.24 

[[3]]
   user  system elapsed 
   3.72    0.16    2.09 

[[4]]
   user  system elapsed 
   3.72    0.14    2.08 

[[5]]
   user  system elapsed 
   3.76    0.15    2.09 

> 
> 
> 
> RcppThreads <- 3
> RcppParallel::setThreadOptions(numThreads = RcppThreads)
> times <- list()
> for (i in 1:5){
+   times[[i]] <- 
+     system.time(parallelMatrixInv(x))
+ }
> print(RcppThreads)
[1] 3
> times
[[1]]
   user  system elapsed 
   3.86    0.19    1.53 

[[2]]
   user  system elapsed 
   3.90    0.10    1.51 

[[3]]
   user  system elapsed 
   3.91    0.14    1.54 

[[4]]
   user  system elapsed 
   3.93    0.12    1.53 

[[5]]
   user  system elapsed 
   3.88    0.14    1.52 

> 
> 
> 
> 
> RcppThreads <- 4
> RcppParallel::setThreadOptions(numThreads = RcppThreads)
> times <- list()
> for (i in 1:5){
+   times[[i]] <- 
+     system.time(parallelMatrixInv(x))
+ }
> print(RcppThreads)
[1] 4
> times
[[1]]
   user  system elapsed 
   3.89    0.17    1.22 

[[2]]
   user  system elapsed 
   4.23    0.10    1.28 

[[3]]
   user  system elapsed 
   4.13    0.11    1.27 

[[4]]
   user  system elapsed 
   4.20    0.11    1.30 

[[5]]
   user  system elapsed 
   4.24    0.13    1.29 

> 
> 
> 
> RcppThreads <- 5
> RcppParallel::setThreadOptions(numThreads = RcppThreads)
> times <- list()
> for (i in 1:5){
+   times[[i]] <- 
+     system.time(parallelMatrixInv(x))
+ }
> print(RcppThreads)
[1] 5
> times
[[1]]
   user  system elapsed 
   4.34    0.22    1.14 

[[2]]
   user  system elapsed 
   4.24    0.17    1.11 

[[3]]
   user  system elapsed 
   4.46    0.17    1.14 

[[4]]
   user  system elapsed 
   4.36    0.13    1.11 

[[5]]
   user  system elapsed 
   4.13    0.19    1.08 

> 
> 
> 
> RcppThreads <- 6
> RcppParallel::setThreadOptions(numThreads = RcppThreads)
> times <- list()
> for (i in 1:5){
+   times[[i]] <- 
+     system.time(parallelMatrixInv(x))
+ }
> print(RcppThreads)
[1] 6
> times
[[1]]
   user  system elapsed 
   4.62    0.09    1.03 

[[2]]
   user  system elapsed 
   4.46    0.11    0.98 

[[3]]
   user  system elapsed 
   4.51    0.16    0.99 

[[4]]
   user  system elapsed 
   4.45    0.14    1.01 

[[5]]
   user  system elapsed 
   4.48    0.20    1.02