$ ./perl -Ilib speed_test.pl 0
time delta = 0.463121175765991

$ ./perl -Ilib speed_test.pl 0
time delta = 0.498654127120972

$ ./perl -Ilib speed_test.pl 0
time delta = 0.462605953216553

$ ./perl -Ilib speed_test.pl 1
time delta = 0.464058876037598
SV = IV(0x83cb27c) at 0x83cb280
  REFCNT = 1
  FLAGS = (TEMP,ROK)
  RV = 0x83cb0f0
  SV = PVAV(0x83bc1b4) at 0x83cb0f0
    REFCNT = 2
    FLAGS = (PADMY)
    ARRAY = 0x83c6180
    FILL = 9
    MAX = 9
    ARYLEN = 0x0
    FLAGS = (REAL)