Sprite kit node not being removed form memory - objective-c

Question

My sprite kit game has been having a memory problem and i have tried everything i know of to fix it but still nothing. A little background on the issue; the first time you play the game, memory is fine, it stays completely stable. But when you die and hit play again, that's when the memory starts creeping up. It seems that the more you play again, the faster the memory creeps up. You can be on any scene and the memory being used will still climb. Here's a picture showing instruments, http://postimg.org/image/5olu8h7tp/.
Here's the code i have:
creates the object:
-(void)createObstacle0 {
int yMin = (CGRectGetMidY(self.frame)+190);
int yMax = (CGRectGetMidY(self.frame)+270);
CGPoint startPoint = CGPointMake(-20, yMin + arc4random_uniform(yMax - yMin));
SKSpriteNode *obstacle = [SKSpriteNode spriteNodeWithImagedNamed:#"obstacle"];
obstacle.position = CGPointMake(startPoint.x, startPoint.y);
obstacle.physicsBody = [SKPhysicsBody bodyWithCircleOfRadius:21];
obstacle.physicsBody.categoryBitMask = enemyCategory;
obstacle.physicsBody.contactTestBitMask = playerCategory;
obstacle.physicsBody.dynamic = NO;
obstacle.name = #"obstacle";
[self addChild:obstacle];
SKAction *move = [SKAction moveTo:CGPointMake(340, startPoint.y) duration:minTime +arc4random_uniform(maxTime - minTime)];
SKAction* removeObstacle = [SKAction removeFromParent];
[obstacle runAction:[SKAction sequence:#[move, removeObstacle]] completion:^{
score++;
scorelabel.text = [NSString stringWithFormat:#"%lu",(unsigned long)score];
}];
float randomNum = arc4random_uniform(3.0) + 0.2;
[self performSelector:#selector(createObstacle0) withObject:nil afterDelay:randomNum];
}
Collision detector and scene transition:
-(void)didBeginContact:(SKPhysicsContact *)contact
{
uint32_t collision = (contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask);
if (collision == (playerCategory | enemyCategory)) {
playerAlive = NO;
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
[defaults setInteger:score forKey:#"playerScore"];
[defaults synchronize];
int highScore = [[[NSUserDefaults standardUserDefaults] objectForKey:#"High Score"] integerValue];
if (highScore){
if (highScore < score){
[[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:score] forKey:#"High Score"];
}
}
else{
[[NSUserDefaults standardUserDefaults] setObject:[NSNumber numberWithInt:score] forKey:#"High Score"];
}
[[NSUserDefaults standardUserDefaults] synchronize];
SKTransition *reveal = [SKTransition fadeWithDuration:0.75];
MGLCreateGameOverScene *scene = [MGLCreateGameOverScene sceneWithSize:self.view.bounds.size];
scene.scaleMode = SKSceneScaleModeAspectFill;
[self.view presentScene:scene transition:reveal];
}
}
To remove remaining nodes:
-(void)update:(CFTimeInterval)currentTime {
if (playerAlive == NO) {
[self enumerateChildNodesWithName:#"obstacle" usingBlock:^(SKNode *node, BOOL *stop) {
[node removeFromParent];
}];
}
}
As i said before, the first time you play, memory stays completely stable. It's only after the first time that memory starts to rise. It appears that the more you revisit the main game scene, the faster the memory climbs. I really need help solving this, my game has been down for two weeks now and i really want it back up. I appreciate all help.

Answer 1

Your problem is with the line:
[self performSelector:#selector(createObstacle0) withObject:nil afterDelay:randomNum];
This method actually retains self (by creating a timer) until after the selector is performed. What you need to do is add to the method didBeginContact: the following line before changing scenes:
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:#selector(createObstacle0) object:nil];
This will destroy the timer that is retaining self and calling that method unendingly.
You can check that this works by adding a call to NSLog(#"%s", __PRETTY_FUNCTION__); in the dealloc method of your scene.