test.lua

function() return error() endlocal socket = require('socket')
local gettime = socket.gettime
local TIMES = 1000000

local t1 = gettime()
for _ = 1, TIMES do
  pcall(error)
end
local t2 = gettime()

local t3 = gettime()
for _ = 1, TIMES do
  pcall(function() return 3 / 1 end)
end
local t4 = gettime()

local t5 = gettime()
for _ = 1, TIMES do
  pcall(function() return 3 / 0 end)
end
local t6 = gettime()

print(t2 - t1, t4 - t3, t6 - t5)

$ eval $(luarocks path --lua-version 5.1)
$ luajit test.lua
1.3156471252441 0.037020921707153       0.037245035171509
$ eval $(luarocks path --lua-version 5.3)
$ lua test.lua
0.14710402488708        0.056612968444824       0.062648057937622