lua/testes/gc.lua
Roberto Ierusalimschy bfcf06d91a Avoid memory allocation in some functions from 'ltests.c'
To allow their use in memory tests, some functions in 'ltests.c'
should never allocate memory. To avoid this allocation, the
library registers the strings used for status codes, and keeps
the variable '_WARN' always defined (with false instead of nil).
2020-07-04 16:40:18 -03:00

682 lines
17 KiB
Lua

-- $Id: testes/gc.lua $
-- See Copyright Notice in file all.lua
print('testing incremental garbage collection')
local debug = require"debug"
assert(collectgarbage("isrunning"))
collectgarbage()
local oldmode = collectgarbage("incremental")
-- changing modes should return previous mode
assert(collectgarbage("generational") == "incremental")
assert(collectgarbage("generational") == "generational")
assert(collectgarbage("incremental") == "generational")
assert(collectgarbage("incremental") == "incremental")
local function nop () end
local function gcinfo ()
return collectgarbage"count" * 1024
end
-- test weird parameters to 'collectgarbage'
do
-- save original parameters
local a = collectgarbage("setpause", 200)
local b = collectgarbage("setstepmul", 200)
local t = {0, 2, 10, 90, 500, 5000, 30000, 0x7ffffffe}
for i = 1, #t do
local p = t[i]
for j = 1, #t do
local m = t[j]
collectgarbage("setpause", p)
collectgarbage("setstepmul", m)
collectgarbage("step", 0)
collectgarbage("step", 10000)
end
end
-- restore original parameters
collectgarbage("setpause", a)
collectgarbage("setstepmul", b)
collectgarbage()
end
_G["while"] = 234
--
-- tests for GC activation when creating different kinds of objects
--
local function GC1 ()
local u
local b -- (above 'u' it in the stack)
local finish = false
u = setmetatable({}, {__gc = function () finish = true end})
b = {34}
repeat u = {} until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
finish = false; local i = 1
u = setmetatable({}, {__gc = function () finish = true end})
repeat i = i + 1; u = tostring(i) .. tostring(i) until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
finish = false
u = setmetatable({}, {__gc = function () finish = true end})
repeat local i; u = function () return i end until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
end
local function GC2 ()
local u
local finish = false
u = {setmetatable({}, {__gc = function () finish = true end})}
local b = {34}
repeat u = {{}} until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
finish = false; local i = 1
u = {setmetatable({}, {__gc = function () finish = true end})}
repeat i = i + 1; u = {tostring(i) .. tostring(i)} until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
finish = false
u = {setmetatable({}, {__gc = function () finish = true end})}
repeat local i; u = {function () return i end} until finish
assert(b[1] == 34) -- 'u' was collected, but 'b' was not
end
local function GC() GC1(); GC2() end
do
print("creating many objects")
local limit = 5000
for i = 1, limit do
local a = {}; a = nil
end
local a = "a"
for i = 1, limit do
a = i .. "b";
a = string.gsub(a, '(%d%d*)', "%1 %1")
a = "a"
end
a = {}
function a:test ()
for i = 1, limit do
load(string.format("function temp(a) return 'a%d' end", i), "")()
assert(temp() == string.format('a%d', i))
end
end
a:test()
end
-- collection of functions without locals, globals, etc.
do local f = function () end end
print("functions with errors")
prog = [[
do
a = 10;
function foo(x,y)
a = sin(a+0.456-0.23e-12);
return function (z) return sin(%x+z) end
end
local x = function (w) a=a+w; end
end
]]
do
local step = 1
if _soft then step = 13 end
for i=1, string.len(prog), step do
for j=i, string.len(prog), step do
pcall(load(string.sub(prog, i, j), ""))
end
end
end
foo = nil
print('long strings')
x = "01234567890123456789012345678901234567890123456789012345678901234567890123456789"
assert(string.len(x)==80)
s = ''
k = math.min(300, (math.maxinteger // 80) // 2)
for n = 1, k do s = s..x; j=tostring(n) end
assert(string.len(s) == k*80)
s = string.sub(s, 1, 10000)
s, i = string.gsub(s, '(%d%d%d%d)', '')
assert(i==10000 // 4)
s = nil
x = nil
assert(_G["while"] == 234)
--
-- test the "size" of basic GC steps (whatever they mean...)
--
do
print("steps")
print("steps (2)")
local function dosteps (siz)
collectgarbage()
local a = {}
for i=1,100 do a[i] = {{}}; local b = {} end
local x = gcinfo()
local i = 0
repeat -- do steps until it completes a collection cycle
i = i+1
until collectgarbage("step", siz)
assert(gcinfo() < x)
return i -- number of steps
end
collectgarbage"stop"
if not _port then
assert(dosteps(10) < dosteps(2))
end
-- collector should do a full collection with so many steps
assert(dosteps(20000) == 1)
assert(collectgarbage("step", 20000) == true)
assert(collectgarbage("step", 20000) == true)
assert(not collectgarbage("isrunning"))
collectgarbage"restart"
assert(collectgarbage("isrunning"))
end
if not _port then
-- test the pace of the collector
collectgarbage(); collectgarbage()
local x = gcinfo()
collectgarbage"stop"
repeat
local a = {}
until gcinfo() > 3 * x
collectgarbage"restart"
assert(collectgarbage("isrunning"))
repeat
local a = {}
until gcinfo() <= x * 2
end
print("clearing tables")
lim = 15
a = {}
-- fill a with `collectable' indices
for i=1,lim do a[{}] = i end
b = {}
for k,v in pairs(a) do b[k]=v end
-- remove all indices and collect them
for n in pairs(b) do
a[n] = undef
assert(type(n) == 'table' and next(n) == nil)
collectgarbage()
end
b = nil
collectgarbage()
for n in pairs(a) do error'cannot be here' end
for i=1,lim do a[i] = i end
for i=1,lim do assert(a[i] == i) end
print('weak tables')
a = {}; setmetatable(a, {__mode = 'k'});
-- fill a with some `collectable' indices
for i=1,lim do a[{}] = i end
-- and some non-collectable ones
for i=1,lim do a[i] = i end
for i=1,lim do local s=string.rep('@', i); a[s] = s..'#' end
collectgarbage()
local i = 0
for k,v in pairs(a) do assert(k==v or k..'#'==v); i=i+1 end
assert(i == 2*lim)
a = {}; setmetatable(a, {__mode = 'v'});
a[1] = string.rep('b', 21)
collectgarbage()
assert(a[1]) -- strings are *values*
a[1] = undef
-- fill a with some `collectable' values (in both parts of the table)
for i=1,lim do a[i] = {} end
for i=1,lim do a[i..'x'] = {} end
-- and some non-collectable ones
for i=1,lim do local t={}; a[t]=t end
for i=1,lim do a[i+lim]=i..'x' end
collectgarbage()
local i = 0
for k,v in pairs(a) do assert(k==v or k-lim..'x' == v); i=i+1 end
assert(i == 2*lim)
a = {}; setmetatable(a, {__mode = 'kv'});
local x, y, z = {}, {}, {}
-- keep only some items
a[1], a[2], a[3] = x, y, z
a[string.rep('$', 11)] = string.rep('$', 11)
-- fill a with some `collectable' values
for i=4,lim do a[i] = {} end
for i=1,lim do a[{}] = i end
for i=1,lim do local t={}; a[t]=t end
collectgarbage()
assert(next(a) ~= nil)
local i = 0
for k,v in pairs(a) do
assert((k == 1 and v == x) or
(k == 2 and v == y) or
(k == 3 and v == z) or k==v);
i = i+1
end
assert(i == 4)
x,y,z=nil
collectgarbage()
assert(next(a) == string.rep('$', 11))
-- 'bug' in 5.1
a = {}
local t = {x = 10}
local C = setmetatable({key = t}, {__mode = 'v'})
local C1 = setmetatable({[t] = 1}, {__mode = 'k'})
a.x = t -- this should not prevent 't' from being removed from
-- weak table 'C' by the time 'a' is finalized
setmetatable(a, {__gc = function (u)
assert(C.key == nil)
assert(type(next(C1)) == 'table')
end})
a, t = nil
collectgarbage()
collectgarbage()
assert(next(C) == nil and next(C1) == nil)
C, C1 = nil
-- ephemerons
local mt = {__mode = 'k'}
a = {{10},{20},{30},{40}}; setmetatable(a, mt)
x = nil
for i = 1, 100 do local n = {}; a[n] = {k = {x}}; x = n end
GC()
local n = x
local i = 0
while n do n = a[n].k[1]; i = i + 1 end
assert(i == 100)
x = nil
GC()
for i = 1, 4 do assert(a[i][1] == i * 10); a[i] = undef end
assert(next(a) == nil)
local K = {}
a[K] = {}
for i=1,10 do a[K][i] = {}; a[a[K][i]] = setmetatable({}, mt) end
x = nil
local k = 1
for j = 1,100 do
local n = {}; local nk = k%10 + 1
a[a[K][nk]][n] = {x, k = k}; x = n; k = nk
end
GC()
local n = x
local i = 0
while n do local t = a[a[K][k]][n]; n = t[1]; k = t.k; i = i + 1 end
assert(i == 100)
K = nil
GC()
-- assert(next(a) == nil)
-- testing errors during GC
if T then
collectgarbage("stop") -- stop collection
local u = {}
local s = {}; setmetatable(s, {__mode = 'k'})
setmetatable(u, {__gc = function (o)
local i = s[o]
s[i] = true
assert(not s[i - 1]) -- check proper finalization order
if i == 8 then error("@expected@") end -- error during GC
end})
for i = 6, 10 do
local n = setmetatable({}, getmetatable(u))
s[n] = i
end
warn("@on"); warn("@store")
collectgarbage()
assert(string.find(_WARN, "error in __gc metamethod"))
assert(string.match(_WARN, "@(.-)@") == "expected"); _WARN = false
for i = 8, 10 do assert(s[i]) end
for i = 1, 5 do
local n = setmetatable({}, getmetatable(u))
s[n] = i
end
collectgarbage()
for i = 1, 10 do assert(s[i]) end
getmetatable(u).__gc = nil
warn("@normal")
end
print '+'
-- testing userdata
if T==nil then
(Message or print)('\n >>> testC not active: skipping userdata GC tests <<<\n')
else
local function newproxy(u)
return debug.setmetatable(T.newuserdata(0), debug.getmetatable(u))
end
collectgarbage("stop") -- stop collection
local u = newproxy(nil)
debug.setmetatable(u, {__gc = true})
local s = 0
local a = {[u] = 0}; setmetatable(a, {__mode = 'vk'})
for i=1,10 do a[newproxy(u)] = i end
for k in pairs(a) do assert(getmetatable(k) == getmetatable(u)) end
local a1 = {}; for k,v in pairs(a) do a1[k] = v end
for k,v in pairs(a1) do a[v] = k end
for i =1,10 do assert(a[i]) end
getmetatable(u).a = a1
getmetatable(u).u = u
do
local u = u
getmetatable(u).__gc = function (o)
assert(a[o] == 10-s)
assert(a[10-s] == undef) -- udata already removed from weak table
assert(getmetatable(o) == getmetatable(u))
assert(getmetatable(o).a[o] == 10-s)
s=s+1
end
end
a1, u = nil
assert(next(a) ~= nil)
collectgarbage()
assert(s==11)
collectgarbage()
assert(next(a) == nil) -- finalized keys are removed in two cycles
end
-- __gc x weak tables
local u = setmetatable({}, {__gc = true})
-- __gc metamethod should be collected before running
setmetatable(getmetatable(u), {__mode = "v"})
getmetatable(u).__gc = function (o) os.exit(1) end -- cannot happen
u = nil
collectgarbage()
local u = setmetatable({}, {__gc = true})
local m = getmetatable(u)
m.x = {[{0}] = 1; [0] = {1}}; setmetatable(m.x, {__mode = "kv"});
m.__gc = function (o)
assert(next(getmetatable(o).x) == nil)
m = 10
end
u, m = nil
collectgarbage()
assert(m==10)
do -- tests for string keys in weak tables
collectgarbage(); collectgarbage()
local m = collectgarbage("count") -- current memory
local a = setmetatable({}, {__mode = "kv"})
a[string.rep("a", 2^22)] = 25 -- long string key -> number value
a[string.rep("b", 2^22)] = {} -- long string key -> colectable value
a[{}] = 14 -- colectable key
assert(collectgarbage("count") > m + 2^13) -- 2^13 == 2 * 2^22 in KB
collectgarbage()
assert(collectgarbage("count") >= m + 2^12 and
collectgarbage("count") < m + 2^13) -- one key was collected
local k, v = next(a) -- string key with number value preserved
assert(k == string.rep("a", 2^22) and v == 25)
assert(next(a, k) == nil) -- everything else cleared
assert(a[string.rep("b", 2^22)] == undef)
a[k] = undef -- erase this last entry
k = nil
collectgarbage()
assert(next(a) == nil)
-- make sure will not try to compare with dead key
assert(a[string.rep("b", 100)] == undef)
assert(collectgarbage("count") <= m + 1) -- eveything collected
end
-- errors during collection
if T then
warn("@store")
u = setmetatable({}, {__gc = function () error "@expected error" end})
u = nil
collectgarbage()
assert(string.find(_WARN, "@expected error")); _WARN = false
warn("@normal")
end
if not _soft then
print("long list")
local a = {}
for i = 1,200000 do
a = {next = a}
end
a = nil
collectgarbage()
end
-- create many threads with self-references and open upvalues
print("self-referenced threads")
local thread_id = 0
local threads = {}
local function fn (thread)
local x = {}
threads[thread_id] = function()
thread = x
end
coroutine.yield()
end
while thread_id < 1000 do
local thread = coroutine.create(fn)
coroutine.resume(thread, thread)
thread_id = thread_id + 1
end
-- Create a closure (function inside 'f') with an upvalue ('param') that
-- points (through a table) to the closure itself and to the thread
-- ('co' and the initial value of 'param') where closure is running.
-- Then, assert that table (and therefore everything else) will be
-- collected.
do
local collected = false -- to detect collection
collectgarbage(); collectgarbage("stop")
do
local function f (param)
;(function ()
assert(type(f) == 'function' and type(param) == 'thread')
param = {param, f}
setmetatable(param, {__gc = function () collected = true end})
coroutine.yield(100)
end)()
end
local co = coroutine.create(f)
assert(coroutine.resume(co, co))
end
-- Now, thread and closure are not reacheable any more.
collectgarbage()
assert(collected)
collectgarbage("restart")
end
do
collectgarbage()
collectgarbage"stop"
collectgarbage("step", 0) -- steps should not unblock the collector
local x = gcinfo()
repeat
for i=1,1000 do _ENV.a = {} end -- no collection during the loop
until gcinfo() > 2 * x
collectgarbage"restart"
end
if T then -- tests for weird cases collecting upvalues
local function foo ()
local a = {x = 20}
coroutine.yield(function () return a.x end) -- will run collector
assert(a.x == 20) -- 'a' is 'ok'
a = {x = 30} -- create a new object
assert(T.gccolor(a) == "white") -- of course it is new...
coroutine.yield(100) -- 'a' is still local to this thread
end
local t = setmetatable({}, {__mode = "kv"})
collectgarbage(); collectgarbage('stop')
-- create coroutine in a weak table, so it will never be marked
t.co = coroutine.wrap(foo)
local f = t.co() -- create function to access local 'a'
T.gcstate("atomic") -- ensure all objects are traversed
assert(T.gcstate() == "atomic")
assert(t.co() == 100) -- resume coroutine, creating new table for 'a'
assert(T.gccolor(t.co) == "white") -- thread was not traversed
T.gcstate("pause") -- collect thread, but should mark 'a' before that
assert(t.co == nil and f() == 30) -- ensure correct access to 'a'
collectgarbage("restart")
-- test barrier in sweep phase (backing userdata to gray)
local u = T.newuserdata(0, 1) -- create a userdata
collectgarbage()
collectgarbage"stop"
local a = {} -- avoid 'u' as first element in 'allgc'
T.gcstate"atomic"
T.gcstate"sweepallgc"
local x = {}
assert(T.gccolor(u) == "black") -- userdata is "old" (black)
assert(T.gccolor(x) == "white") -- table is "new" (white)
debug.setuservalue(u, x) -- trigger barrier
assert(T.gccolor(u) == "gray") -- userdata changed back to gray
collectgarbage"restart"
print"+"
end
if T then
local debug = require "debug"
collectgarbage("stop")
local x = T.newuserdata(0)
local y = T.newuserdata(0)
debug.setmetatable(y, {__gc = nop}) -- bless the new udata before...
debug.setmetatable(x, {__gc = nop}) -- ...the old one
assert(T.gccolor(y) == "white")
T.checkmemory()
collectgarbage("restart")
end
if T then
print("emergency collections")
collectgarbage()
collectgarbage()
T.totalmem(T.totalmem() + 200)
for i=1,200 do local a = {} end
T.totalmem(0)
collectgarbage()
local t = T.totalmem("table")
local a = {{}, {}, {}} -- create 4 new tables
assert(T.totalmem("table") == t + 4)
t = T.totalmem("function")
a = function () end -- create 1 new closure
assert(T.totalmem("function") == t + 1)
t = T.totalmem("thread")
a = coroutine.create(function () end) -- create 1 new coroutine
assert(T.totalmem("thread") == t + 1)
end
-- create an object to be collected when state is closed
do
local setmetatable,assert,type,print,getmetatable =
setmetatable,assert,type,print,getmetatable
local tt = {}
tt.__gc = function (o)
assert(getmetatable(o) == tt)
-- create new objects during GC
local a = 'xuxu'..(10+3)..'joao', {}
___Glob = o -- ressurrect object!
setmetatable({}, tt) -- creates a new one with same metatable
print(">>> closing state " .. "<<<\n")
end
local u = setmetatable({}, tt)
___Glob = {u} -- avoid object being collected before program end
end
-- create several objects to raise errors when collected while closing state
if T then
local error, assert, find, warn = error, assert, string.find, warn
local n = 0
local lastmsg
local mt = {__gc = function (o)
n = n + 1
assert(n == o[1])
if n == 1 then
_WARN = false
elseif n == 2 then
assert(find(_WARN, "@expected warning"))
lastmsg = _WARN -- get message from previous error (first 'o')
else
assert(lastmsg == _WARN) -- subsequent error messages are equal
end
warn("@store"); _WARN = false
error"@expected warning"
end}
for i = 10, 1, -1 do
-- create object and preserve it until the end
table.insert(___Glob, setmetatable({i}, mt))
end
end
-- just to make sure
assert(collectgarbage'isrunning')
collectgarbage(oldmode)
print('OK')