lua gc test case

case1.lua

local count = 10000
local items = 10000

local g = {}
collectgarbage("stop")
function run_gc_test(tag, mt)
  for i=1,count do
    local t = {}
    if mt then
      setmetatable(t, mt)
    end
    for j=1,items do
      t[j] = {}
    end
    g[#g+1] = t
  end

  local mem = collectgarbage("count")
  print(tag, "memory size before gc:", mem)

  local finished
  while not finished do
    local t0 = os.clock()
    finished = collectgarbage("step", 100000)
    local t1 = os.clock()
    print(tag, "table gc step, consumed:",finished, t1-t0)
  end

  local mem = collectgarbage("count")
  print(tag, "memory size after gc:", mem)
end

for i=1, 50 do
  print("======== round", i)
  --run_gc_test("gc metamethod", {__gc=function(o) end})
  run_gc_test("simple")
  --run_gc_test("weak table", {__mode="v"})
end

log.txt

======== round	1
simple	memory size before gc:	8029580.5449219
++++++ gcstate: 7 -> 0 +++++++
simple	table gc step, consumed:	false	0.08023
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.038946000000003
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.053604
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.046549000000002
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.045299999999997
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.046872999999998
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.049885
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.052053000000001
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.047357999999999
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.046369000000002
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.051092000000001
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.048818000000001
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.047307
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.045746999999999
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.052253999999998
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.041041
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.058584
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.185741
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.249438
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.21657
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.224915
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.236445
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.214558
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.186554
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.188677
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.208974
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.218669
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.210864
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.208496
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.205281
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.208982
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.212862
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.210816
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.212025
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.21422
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.209858
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.210246
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.220917
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.256822
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.314258
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.286934
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.241109
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.21705
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.234824
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.220309
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.222933
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.223696
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.226823
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.227693
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.223481
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.222663
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.226209
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.2347
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.225192
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.238531
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.259061
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.223961
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.229892
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.235737
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.23717
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.231842
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.229655
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.218181
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.221824
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.225791
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.226298
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.22205
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.222908
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.223668
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.217165
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.224236
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.224186
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.218289
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.213076
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.220979
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.223594
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.217259
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.216023
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.222395
++++++ gcstate: 0 -> 0 +++++++
simple	table gc step, consumed:	false	0.217481
++++++ gcstate: 0 -> 2 +++++++
simple	table gc step, consumed:	false	1.307541
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.731343
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.711169
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.760332
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.770299
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.714799
++++++ gcstate: 2 -> 2 +++++++
simple	table gc step, consumed:	false	1.744867
++++++ gcstate: 2 -> 7 +++++++
simple	table gc step, consumed:	true	0.232102
simple	memory size after gc:	8029580.4863281