Random Server Crashes..

[pooty]

So the one crash today, end of round, I typed 'teams' during the countdown and boom. Might be coincidence but right after I hit return music stopped and it crashed. I definitely think its releated to teams/people coming going during mid rounds.

[FuriousRabbit]

Just make it so people aren't allowed to quit. That'll also solve the problem with not having enough players.

[Enyo]

So the one crash today, end of round, I typed 'teams' during the countdown and boom. Might be coincidence but right after I hit return music stopped and it crashed. I definitely think its releated to teams/people coming going during mid rounds.

Crashes happen too sometimes when people join/leave between rounds. Is it maybe evenmatch that's getting tripped up by that?

[pooty]

So last night we crashed at end of round on AJY, and someone did leave. I found this snippet as the last line of the log

Warning: UTComp_ONSGameRules ONS-ArcticJunkYard-)o(-Randomizer-V24.UTComp_ONSGameRules (Function UTCo

It cut off like that, but I noticed in that class, Two functions that maybe a place to look.
Which might be CheckScores?

Warning: UTComp_ONSGameRules ONS-AratheiaC)o(mplex-V2.UTComp_ONSGameRules (Function UTCompOmni.UTComp_ONSGameRules.CheckScore:01C7) Accessed None 'C'
Which we've seen a bunch in the logs.
Also in conjuntion with
Warning: UAMGameRules ONS-AratheiaC)o(mplex-V2.UAMGameRules (Function UAdminModV095b.UAMGameRules.PreventDeath:002F) Accessed None 'Controller'



Function NavigationPoint
which changes the playerstarts, which might be related to this warning

Warning: SpawnActor failed because class Pawn is abstract
ScriptLog: Couldn't spawn player of type UTCompOmni.UTComp_xPawn at ONS-Dria-Randomizer-V21.PlayerStart37
Although I think we figured this wasn't a cause.

But back to CheckScores code

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// snarf attempt to fix the after round shenanigans
function bool CheckScore(PlayerReplicationInfo Scorer)
{
    local PlayerController PC;
    local Controller C;
    local ONSOnslaughtGame ONS;
    local int deadCore;
    local bool retval;

    retval = false;
    if(NextGameRules != none)
        retval = NextGameRules.CheckScore(Scorer);

    deadCore = -1;
    ONS = ONSOnslaughtGame(Level.Game);
    if(ONS != none && ONS.PowerCores[ONS.FinalCore[0]].Health <= 0)
        deadCore = 0;
    else if(ONS != none && ONS.PowerCores[ONS.FinalCore[1]].Health <= 0)
        deadCore = 1;

        //round has ended
    if(deadCore >= 0)
    {
        for (C = Level.ControllerList; C != None; C = C.NextController)
        {
            PC = PlayerController(C);
            if (PC != None)
            {
                PC.ClientSetBehindView(true);
                PC.ClientSetViewTarget(ONS.PowerCores[ONS.FinalCore[deadCore]]);
                PC.SetViewTarget(ONS.PowerCores[ONS.FinalCore[deadCore]]);
                PC.ClientRoundEnded();

            }

            if(C != None)
                C.RoundHasEnded();
        }
    }

    return retval;
}

Only spot I can see where accessing C = None would be PC=PlayerController(C) (Player Controller being the player, but what if they leave? Note: this construct is used quite a bit in engine.gameinfo ( http://kos.informatik.uni-osnabrueck.de ... einfo.html )

So maybe we need two more checks:

Code: Select all

[b] for (C = Level.ControllerList; C != None; C = C.NextController)
        {
           if ( C != None)  // this should be unecessary based on for loop but only spot where C could be accessed and be none.
            	PC = PlayerController(C);
           
           if ((PC != None) && P.IsA('PlayerController')) // Saw that check in engine.gameinfo, is it possible for PC to be non Player and PC.ClientSet functions fail causing a crash?
            {
                PC.ClientSetBehindView(true);
                PC.ClientSetViewTarget(ONS.PowerCores[ONS.FinalCore[deadCore]]);
                PC.SetViewTarget(ONS.PowerCores[ONS.FinalCore[deadCore]]);
                PC.ClientRoundEnded();

            }

            if(C != None)
                C.RoundHasEnded();
                
        }[/b]

Snarf, what do you think?

[captainsnarf]

I think I need to change it to use a while loop instead of for loop.

Code: Select all

 for (C = Level.ControllerList; C != None; C = C.NextController)
 {
 }

If Level.ControllerList is None, then this for loop will cause a 'Accessed None' error when it tries to execute 'C = C.NextController'.

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for(expression A;expression B; expression C) { ... }

expression A is executed first. At the end of the loop, expression C is executed. Before entering the loop again, expression B is checked for true. If false the looping is over.

Level.ControllerList is a linked list. Generally you use a while loop for those.

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local Controller C;
C = Level.ControllerList;
while(C != None) 
{
   ... 
   C = C.NextController;
}

The for loop was copy/paste from existing engine code, so I thought it would work.

this is unnecessary

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if(C != None)
  PC = PlayerController(C);

It's safe to do

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PC = PlayerController(None);

This will result in PC = None also, not 'Accessed None' error.

Player Controller being the player, but what if they leave?

As far as I understand this is all single threaded. This function will execute in its entirety before processing any players that leave. It should be a non-issue.

[pooty]

As far as I understand this is all single threaded. This function will execute in its entirety before processing any players that leave. It should be a non-issue.

Should be.. but somewhere something is getting messed up.. I am fairly certain it has to do with timing of a player leaving usually right at the end of the round (before the countdown of 1...2...3).

[captainsnarf]

We were playing Valarna last night and a few players dropped. Enyo nope'd out between rounds and bam.. another crash. I posted a new version of UTCompOmni with that 'for' loop changed to a 'while' loop to avoid the possible None reference discussed above.

[pooty]

Yep saw that. I'll get the new version up. I think if it still crashes, maybe we start to focus on EvenMatch. (or UAdminMod but we don't have the source for that) - those two care about team sizes.

[captainsnarf]

Sadly, we are still having crashes. I checked the logs and this is the main error:

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Warning: Other object in slot
Warning: Other is: NewNet_AssaultGrenade ONS-Valarna-Randomizer-V7.NewNet_AssaultRifle.NewNet_AssaultGrenade385
Warning: This is: TcpipConnection Package.TcpipConnection
Critical: Assertion failed: IsValid() [File:.\UnObj.cpp] [Line: 464]
Exit: Executing UObject::StaticShutdownAfterError

The warning 'Other object in slot' comes from the IsValid() function. That is called from the destructor for the the object (line 464 of UnObj.cpp).

This is still there also.

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Warning: UTComp_ONSGameRules ONS-Valarna-Randomizer-V7.UTComp_ONSGameRules (Function UTCompOmni.UTComp_ONSGameRules.CheckScore:01D2) Accessed None 'C'

I don't think it's the problem though. It's definitely UTComp, but not this function.

[pooty]

It seems about 1 a night, 1 every other night or so. I've also noticed besides it being an end of round thing, I always seem to get much more lag just before it happens... meaning there will be a round with a bunch of lag/slowness and shortly afterwards..boom. I wonder if its a memory leak somewhere?