Operation x=x/3+3 on array of 1 000 000 int
Tests on Macbook Air 2,2 GHz Intel Core i7, 8 Go 1600 MHz DDR3
With clang v10 C -O3
Finish '<' 365ms '!=' 371ms '--' 425ms total:1162ms
Finish '<' 386ms '!=' 381ms '--' 432ms total:1200ms
Finish '<' 372ms '!=' 359ms '--' 416ms total:1148ms
Finish '<' 370ms '!=' 355ms '--' 418ms total:1144ms
Finish '<' 425ms '!=' 476ms '--' 478ms total:1380ms
Finish '<' 449ms '!=' 473ms '--' 500ms total:1423ms
Finish '<' 388ms '!=' 376ms '--' 461ms total:1225ms
Finish '<' 424ms '!=' 471ms '--' 440ms total:1336ms
Finish '<' 375ms '!=' 352ms '--' 495ms total:1222ms
Finish '<' 467ms '!=' 400ms '--' 424ms total:1291msWith clang v10 C -O3 -march=native
Finish '<' 282ms '!=' 254ms '--' 288ms total:825ms
Finish '<' 268ms '!=' 253ms '--' 298ms total:820ms
Finish '<' 272ms '!=' 256ms '--' 298ms total:826ms
Finish '<' 286ms '!=' 264ms '--' 303ms total:854ms
Finish '<' 279ms '!=' 264ms '--' 296ms total:841ms
Finish '<' 276ms '!=' 254ms '--' 305ms total:836ms
Finish '<' 275ms '!=' 262ms '--' 302ms total:840ms
Finish '<' 280ms '!=' 263ms '--' 309ms total:853ms
Finish '<' 269ms '!=' 254ms '--' 297ms total:821ms
Finish '<' 269ms '!=' 254ms '--' 289ms total:813msWith clang v10 C++ -O3
Finish c-style: 422ms 361ms 409ms valarray: 362ms vector: 354ms 348ms 353ms total:2613ms
Finish c-style: 367ms 368ms 403ms valarray: 378ms vector: 361ms 358ms 360ms total:2597ms
Finish c-style: 371ms 364ms 412ms valarray: 356ms vector: 359ms 370ms 373ms total:2608ms
Finish c-style: 391ms 362ms 409ms valarray: 356ms vector: 349ms 350ms 364ms total:2585ms
Finish c-style: 369ms 372ms 404ms valarray: 364ms vector: 352ms 352ms 354ms total:2570ms
Finish c-style: 362ms 354ms 432ms valarray: 354ms vector: 360ms 362ms 348ms total:2575ms
Finish c-style: 361ms 355ms 397ms valarray: 355ms vector: 350ms 351ms 351ms total:2523ms
Finish c-style: 377ms 360ms 431ms valarray: 358ms vector: 350ms 351ms 348ms total:2578ms
Finish c-style: 375ms 362ms 413ms valarray: 366ms vector: 352ms 350ms 350ms total:2572ms
Finish c-style: 372ms 364ms 414ms valarray: 350ms vector: 359ms 359ms 360ms total:2580msWith clang v10 C++ -O3 -march=native
Finish c-style: 279ms 306ms 307ms valarray: 283ms vector: 285ms 289ms 279ms total:2031ms
Finish c-style: 295ms 335ms 314ms valarray: 295ms vector: 290ms 303ms 288ms total:2124ms
Finish c-style: 285ms 306ms 307ms valarray: 276ms vector: 285ms 286ms 284ms total:2032ms
Finish c-style: 311ms 352ms 332ms valarray: 276ms vector: 293ms 293ms 294ms total:2154ms
Finish c-style: 289ms 310ms 309ms valarray: 272ms vector: 279ms 285ms 283ms total:2031ms
Finish c-style: 294ms 320ms 319ms valarray: 276ms vector: 278ms 275ms 272ms total:2039ms
Finish c-style: 283ms 310ms 307ms valarray: 276ms vector: 295ms 292ms 294ms total:2060ms
Finish c-style: 317ms 315ms 317ms valarray: 277ms vector: 278ms 298ms 281ms total:2088ms
Finish c-style: 285ms 315ms 313ms valarray: 274ms vector: 281ms 277ms 277ms total:2025ms
Finish c-style: 285ms 308ms 305ms valarray: 287ms vector: 279ms 277ms 279ms total:2023msUsed command in blaar
./compile test_optim
for i in {1..10}; do bin/test_c; done;`
for i in {1..10}; do bin/test_cpp; done;`The compile flags are in the respective CMakeLists.txt files. -O3 -DNDEBUG is the default.
In DEBUG mode the containers are much slower that in simple c-style.
With g++ v9 C++ -O3 -march=native
Finish c-style: 221ms 213ms 275ms valarray: 303ms vector: 224ms 219ms 221ms total:1680ms
Finish c-style: 266ms 259ms 332ms valarray: 293ms vector: 222ms 219ms 215ms total:1808ms
Finish c-style: 223ms 212ms 277ms valarray: 312ms vector: 218ms 211ms 214ms total:1669ms
Finish c-style: 216ms 211ms 264ms valarray: 287ms vector: 222ms 249ms 253ms total:1706ms
Finish c-style: 254ms 247ms 275ms valarray: 311ms vector: 222ms 220ms 220ms total:1752ms
Finish c-style: 240ms 225ms 277ms valarray: 523ms vector: 330ms 236ms 254ms total:2089ms
Finish c-style: 229ms 222ms 277ms valarray: 359ms vector: 231ms 224ms 245ms total:1790ms
Finish c-style: 235ms 220ms 279ms valarray: 301ms vector: 224ms 219ms 242ms total:1722ms
Finish c-style: 278ms 278ms 328ms valarray: 302ms vector: 215ms 228ms 316ms total:1949ms
Finish c-style: 222ms 216ms 351ms valarray: 386ms vector: 249ms 303ms 224ms total:1954ms