Benchmark: timing 5 iterations of FastMktime::caching_mktime, FastMktime::new_caching_mktime, POSIX::mktime, TIME::Local::timegm_nocheck... FastMktime::caching_mktime: 65 wallclock secs (64.36 usr + 0.02 sys = 64.38 CPU) @ 0.08/s (n=5) FastMktime::new_caching_mktime: 220 wallclock secs (157.44 usr + 62.10 sys = 219.54 CPU) @ 0.02/s (n=5) POSIX::mktime: 122 wallclock secs (60.43 usr + 60.86 sys = 121.29 CPU) @ 0.04/s (n=5) TIME::Local::timegm_nocheck: 141 wallclock secs (140.86 usr + 0.30 sys = 141.16 CPU) @ 0.04/s (n=5)