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Time::timestamp -> Integer
Returns a nanosecond-precision timestamp from the system’s monotonic clock. Note that the resolution of the measured time is system- dependent (i.e. while the value displayed is always an integer number of nanoseconds, the values may not necessarily change in increments of exactly one).
This time value does not correlate to any absolute, real-world time system; it is only useful for measuring relative (or elapsed) times at a high granularity. For example, benchmark measurements.
Time::unix_timestamp -> Integer Time::unix_time -> Integer
Returns the current real-world time as a whole number of seconds since the Epoch (1-Jan-1970).
Time::unix_microtime -> Float
Returns the current real-world time as a floating-point number of seconds since the Epoch (1-Jan-1970).