About ios memory management issues

sdk is ios6.1, do not open the ARC.

 
# Import  
# Import  

- (Id) init 
{
self = [super init]; 
[Self usedMemory]; 
[Self addtitle: @ "d"]; 
[Self usedMemory]; 
return self; 
} 

- (Void) addtitle: (NSString *) title 
{
for (double i = 0; i <200000; i + +) {

/ / NSString * T2 = [@ ">" stringByAppendingString: title]; 

NSObject * T2 = [[NSObject alloc] init]; 
[T2 release]; 
} 
} 

- (Void) usedMemory 
{
task_basic_info_data_t taskInfo; 
mach_msg_type_number_t infoCount = TASK_BASIC_INFO_COUNT; 
kern_return_t kernReturn = task_info (mach_task_self (), 
TASK_BASIC_INFO, 
(Task_info_t) & taskInfo, 
& InfoCount); 

if (kernReturn! = KERN_SUCCESS 
) {
NSLog (@ "Nofound"); 
} 

NSLog (@ "Memery% f", taskInfo.resident_size / 1024.0 / 1024.0);; 
} 

The result:
2013-09-14 18:56:24.240 menerytest [5913: c07] Memery16.789062
2013-09-14 18:56:24.281 menerytest [5913: c07] Memery17.128906

If [T2 release]; commented:
2013-09-14 19:05:41.786 menerytest [6476: c07] Memery16.890625
2013-09-14 19:05:41.804 menerytest [6476: c07] Memery20.320312

Originally T2 used is NSString * T2 = [@ ">" stringByAppendingString: title];
Memory does not release a substantial growth, growth release memory after the first result similar to the above, but the program will eventually crash out.
Why release a memory leak or fall out? Although quite small. And why "[@"> "stringByAppendingString: title]" After the release will crash it?

Reply:
stringByAppendingString: title returns the NSString already autorelease, you no longer need to manually release
Reply:
You lost the excessive release
Reply:
Thanks a floor, but I still want to know

NSObject * T2 = [[NSObject alloc] init];
[T2 release];

This tiny memory go between the
Reply:

Reply:
[Self usedMemory];
NSAutoreleasePool * pool = [NSAutoreleasePool new];
.....
[Pool release];
[Self usedMemory];

You try this.
Reply:

references, 5th Floor zx119koko reply:

[self usedMemory];
NSAutoreleasePool * pool = [NSAutoreleasePool new];
.....
[Pool release];
[Self usedMemory];

You try this.

Testing is still the same, but also tested with
@ Autoreleasepool {

for (double i = 0; i <200000; i + +)
{
NSObject * T2 = [[NSObject alloc] init];
[T2 release];
}

}


Reply:
I see, I do not speak
Reply:
You do not need to release NSString above the bar
Reply:

The reply was deleted administrator at 2013-09-24 13:19:23

Reply:

reference to the third floor u010129860 reply:

Thanks a floor, but I still want to know

NSObject * T2 = [[NSObject alloc] init];
[T2 release];

This tiny memory go between the

You do not care about this, so then you do not divulge it.