???????????????????????????

????????
????gcc fork.c -o fork -Wall
????gcc pthread_create.c -o pthread_create -Wall
???????
??????????????
????$ cat /proc/cpuinfo | grep name | uniq
????model name : AMD Athlon(tm) 64 X2 Dual Core Processor 5200+
????$ uname -a
????Linux Mint 3.16.0-36-generic #48~14.04.1-Ubuntu SMP Wed Apr 15 13:11:28 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
?????????????????????????
????$ time ./fork
????real 0m12.539s
????user 0m0.124s
????sys 0m13.070s
?????????????????????????
????$ time ./pthread_create
????real 0m1.995s
????user 0m0.503s
????sys 0m1.821s