x64
found = 16225993 0.37 real 0.33 user 0.03 sys
found = 16225993 0.39 real 0.31 user 0.06 sys
found = 16225993 0.40 real 0.24 user 0.13 sys
found = 16225993 0.39 real 0.28 user 0.09 sys
found = 16225993 0.39 real 0.26 user 0.11 sys
found = 16225993 0.39 real 0.29 user 0.08 sys
found = 16225993 0.39 real 0.27 user 0.10 sys
found = 16225993 0.39 real 0.30 user 0.06 sys
found = 16225993 0.39 real 0.30 user 0.06 sys
found = 16225993 0.39 real 0.27 user 0.10 sys

x86
found = 16225993 0.81 real 0.06 user 0.72 sys
found = 16225993 0.83 real 0.03 user 0.77 sys
found = 16225993 0.80 real 0.01 user 0.77 sys
found = 16225993 0.82 real 0.03 user 0.77 sys
found = 16225993 0.80 real 0.06 user 0.72 sys
found = 16225993 0.83 real 0.03 user 0.78 sys
found = 16225993 0.81 real 0.02 user 0.77 sys
found = 16225993 0.82 real 0.03 user 0.76 sys
found = 16225993 0.80 real 0.03 user 0.74 sys
found = 16225993 0.83 real 0.06 user 0.74 sys

コマンドだのスクリプトだの使わなければ、一回キャッシュに入れば１秒も掛からない
にしても、たまたまハマったのか、このサンプルコードはx64がえっれーはえーな