hattom / setmat_threaded

setmat_threaded

How best to accelerate (with threads) some matrix assembly code where the array access pattern is complicated.

Proxy application for assembling an FEM matrix with a Lapack general banded representation.

Output

$ make; export OMP_NUM_THREADS=4; ./test_setmat
gfortran -c -o obj/band_data.o -O3 -fopenmp band_data.F90
gfortran -c -o obj/test_setmat.o -O3 -fopenmp test_setmat.F90
gfortran -o test_setmat -O3 -fopenmp  obj/test_setmat.o obj/band_data.o
 Early SINE
   10.319533966154633        20.054816200048663
   10.374677401430977        5.4544377999845892
   10.319533966154346        7.4213781000580639
   10.319533966154633        15.378228500019759
   10.319533966154633        25.649740899913013
 Late SINE
   10.319533966154633        24.450728600029834
   10.319533966154452        6.4496109999017790
   10.319533966154490        8.0782184000127017
   10.319533966154633        15.564078600029461
   10.319533966154633        15.605280900024809

The first column is the result, the second column is the time taken. The 5 different rows in a section are 5 methods, the 2 sections are whether the intermediate results are calculated immediately, or in the inner loop.