[jon@valium jon]$ ./test.pl Benchmark: timing 10000000 iterations of double, single... double: 1 wallclock secs ( 1.91 usr + 0.00 sys = 1.91 CPU) @ 5235602.09/s (n=10000000) single: 2 wallclock secs ( 1.25 usr + 0.00 sys = 1.25 CPU) @ 8000000.00/s (n=10000000) Rate double single double 5235602/s -- -35% single 8000000/s 53% --