12.34

matrix size and thread number

!INCLUDE "./code/12.34.h"

non concurrent version

!INCLUDE "./code/12.34.non.concurrent.c"

concurrent version

!INCLUDE "./code/12.34.concurrent.c"

measure performance

(cd chapter12/code; make clean && make && make measure)

output

(time ./12.34.non.concurrent)
0.90user 0.00system 0:00.90elapsed 99%CPU (0avgtext+0avgdata 3704maxresident)k
0inputs+0outputs (0major+756minor)pagefaults 0swaps
// single cpu run time 0.9s
(time ./12.34.concurrent)
2.20user 0.00system 0:00.64elapsed 341%CPU (0avgtext+0avgdata 3896maxresident)k
0inputs+0outputs (0major+1462minor)pagefaults 0swaps
// 4 cpu, total run time 2.2s(every cpu run 0.55s, concurrent!!)

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