measure Lua code speed

simple_lua_profile.lua

local t_sum = 0
local t_num = 0
local t1, t2, t3
local do_time = true

local function mark1()
  if not do_time then return end
  t1 = os.clock()
end

local function mark2()
  if not do_time then return end
  t2 = os.clock()
end

local function mark3()
  if not do_time then return end
  t3 = os.clock()

  print('---')
  print(string.format('t1-t3 took %gs', t3 - t1))
  print(string.format('t1-t2 took %gs', t2 - t1))
  print(string.format('t2-t3 took %gs', t3 - t2))

  t_sum = t_sum + t3 - t1
  t_num = t_num + 1
  print(string.format('avg t1-t3 is now %gs', t_sum / t_num))
end

This is a super-fast kinda-hacky way to measure the speed of a section of Lua code.

Call mark1, mark2, and mark3 in order. The intended use case is to either isolate a bottleneck - decided between the first or second interval measured - or to get an absolute measure of the average run time of the code between mark1 and mark3.