minetest.get us time

Description
Returns time with microsecond precision. This does not seem to be strictly related to game time or time of day in a meaningful way, but should be useful for taking differences in time measured during a single execution of the server. For example, it can be useful for profiling mod performance. According to the benchmark test (see below) it works about twice as fast as os.clock.

Examples
to get time differences, minetest.get_us_time seems to works faster than os.clock: benchmark_function from Lua_Optimization_Tips