New Leak Found: Keeping references to destroyed objects.

[Jesus4Lyf]

These are memory leaks (but not handle id leaks). You must check the process list to see it leak.
Credits to Troll-Brain for finding the original leak.

This leaks:

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

private function DoTheTest takes nothing returns nothing
    //call BJDebugMsg("run")
    set G1=null // With or without this line.
    set G1=CreateGroup()
    call DestroyGroup(G1)
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.0,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

In fact, even this leaks:

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

globals
    boolean k=false
endglobals

private function DoTheTest takes nothing returns nothing
    //call BJDebugMsg("run")
    if k then
        set G1=null
    else
        set G1=CreateGroup()
        call DestroyGroup(G1)
    endif
    set k = not k
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.01,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

This does not leak:

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

private function DoTheTest takes nothing returns nothing
    //call BJDebugMsg("run")
    set G1=CreateGroup()
    call DestroyGroup(G1)
    set G1=null
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.0,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

What's the exact cause? Discuss. I will update this post as conclusions are reached and verified.

This is a minor leak.

Conclusion:
Not allowing a handle id to be recycled immediately after destruction causes a memory leak.

 

[Jesus4Lyf]

I have a new conclusion. We know that the handle id recycler will pick up a handle at any point after it has been destroyed, when its reference count hits 0.

Well, it seems if that is not immediately after it is destroyed, then it causes a leak.

I conclude this because setting the variable to "GROUP" (a constant group) also stops the leak.

Edit: Yep.
Does not leak:

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

private function OtherTest takes nothing returns nothing
    local group g=CreateGroup()
    call DestroyGroup(g)
    set g=null
    call TriggerSleepAction(0)
endfunction

private function DoTheTest takes nothing returns nothing
    //call BJDebugMsg("run")
    call OtherTest.execute()
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.0,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

Does leak:

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

private function OtherTest takes nothing returns nothing
    local group g=CreateGroup()
    call DestroyGroup(g)
    call TriggerSleepAction(0)
    set g=null
endfunction

private function DoTheTest takes nothing returns nothing
    //call BJDebugMsg("run")
    call OtherTest.execute()
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.0,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

 

[T.s.e]

I still don't see why you would want to destroy a global group, but it is probably an example that applies to handles in general?

 

[Jesus4Lyf]

Occurs for all agents. Local and global.

Updated the original post with the new conclusion.

 

[Zwiebelchen]

So the conclusion is: Even globals have to be nulled after destruction.

One question: Does this leak? If yes, then globals have to be nulled immediately and not only inside the same instance.

set G1 = CreateGroup()
call DestroyGroup(G1)
call DoNothing()
set G1 = null

 

[Jesus4Lyf]

This also leaks (demo using hashtables):

Spoiler

library Test initializer init

globals
    private group G1
    private group G2
    private group GROUP=CreateGroup()
    private trigger Trig
    private hashtable H=InitHashtable()
endglobals

private function Actions takes nothing returns nothing
    call BJDebugMsg("Start")
    call EnableTrigger(Trig)
    call TriggerSleepAction(10.)
    call DisableTrigger(Trig)
    call BJDebugMsg("End")
endfunction

private function DoTheTest takes nothing returns nothing
    call SaveGroupHandle(H,0,0,CreateGroup())
    call DestroyGroup(LoadGroupHandle(H,0,0))
endfunction

private function init takes nothing returns nothing
    local trigger trig = CreateTrigger()
    set Trig = CreateTrigger()
    
    call TriggerRegisterTimerEvent(Trig,0.0,true)
    call TriggerAddAction(Trig,function DoTheTest)
    call DisableTrigger(Trig)
    
    call TriggerRegisterPlayerEventEndCinematic(trig,Player(0))
    call TriggerAddAction(trig, function Actions)
endfunction

endlibrary

This does not leak (hashtables):

Spoiler

private function DoTheTest takes nothing returns nothing
    call SaveGroupHandle(H,0,0,CreateGroup())
    call DestroyGroup(LoadGroupHandle(H,0,0))
    call SaveGroupHandle(H,0,0,GROUP)
endfunction

Neither does this:

private function DoTheTest takes nothing returns nothing
    call SaveGroupHandle(H,0,0,CreateGroup())
    call DestroyGroup(LoadGroupHandle(H,0,0))
    call RemoveSavedHandle(H,0,0)
endfunction

>One question: Does this leak? If yes, then globals have to be nulled immediately
No, it does not (tested). But remember, nulling after a wait does (if the handle is removed during the wait).

So the conclusion is solid?

 

[kingkingyyk3]

Tested. Setting a variable(contains destroyed value) to a new value will cause leaking.

 

[Jesus4Lyf]

Tested. Setting a variable(contains destroyed value) to a new value will cause leaking.

...
...
Unless it is done after destruction and before a wait.

 

[Azlier]

Blizzfail detected.

 

[kingkingyyk3]

1.25 patch?

 

[Azlier]

Nay, Blizzard only fixes things that affect their income. Virus maps, yeah, suing could happen there. But a minor memory leak that people found out about eight years later? I don't think so.

 

[T.s.e]

Then why did they fix local masking? I can't see how that would affect their income.

 

[Viikuna]

Actually, according to Vexorian, local masking works perfectly now. ( link )

Noone really knows what Blizzard is doing and why...

 

[Azlier]

>Then why did they fix local masking?

Because apparently typecasting could be done via shadowing. So Blizzard decided to fixit. Or something.

 

[uberfoop]

I guess that at least (partially) explains the slow memory increases of supposedly leak free maps that aren't increasing in active object count.

On the plus side, these leaks are tiny and generally preventable.

 

[Troll-Brain]

>Then why did they fix local masking?

Because apparently typecasting could be done via shadowing. So Blizzard decided to fixit. Or something.

Yes it could be done :

http://www.wc3c.net/showthread.php?t=98230

 

[Lyerae]

Oh hey look, a new leak...
Just another thing I need to learn how to fix. OH WELL.

 

[Troll-Brain]

Oh hey look, a new leak...
Just another thing I need to learn how to fix. OH WELL.

It's not that hard, just set to null the handle variable just after you have destroyed the handle, or flush gamecache/hashtable if you used it instead of a variable.

According to Jesus4Lyf you might can do it after few lines of code without waits, but i recommend to set to null in the line just below the handle destruction, just to be sure, at least it's more likely you won't forget it.

 

[Lyerae]

Yeah, well... It's still another thing to remember. And I'm really bad at remembering...

 

[uberfoop]

If you just recycle what can be recycled in a practical manner you should be fine. That's more efficient anyway than create and destroy, and results in cleaner end code (ie no need to null anything). Global group + GroupClear for instant-use groups, GroupUtils or some other recycler for other groups, TU and maybe T32 for timers depending on what you are doing/need, etc.