Massive allocations with with CFString while writing to NSOutputStream in iOS - ios

Question

I have problem with large number of allocations while writing to NSOutputStream. I am using few classes together that are supposed to stream data from AudioUnit to remote server. Code below:
AudioProcessor.m
Data *data = [Data sharedData]; //it's shared data I use to store information for the final socket
intFromBuffer = audioBufferList->mBuffers[0].mData;
NSUInteger length = audioBufferList->mBuffers[0].mDataByteSize;
NSMutableData *dataOut = [[NSMutableData alloc] initWithCapacity:0];
[dataOut appendBytes:(const void *)intFromBuffer length:length * sizeof(SInt16)];
[data setOutput:dataOut]; //it writes data to the shared data
Data.m
#implementation Data
NSMutableData *output;
NSMutableData *input;
#synthesize output;
#synthesize input;
+(id)sharedData {
static Data *sharedData = nil;
#synchronized(self) {
if (sharedData == nil) {
sharedData = [[self alloc] init];
}
return sharedData;
}
}
-(void) setOutput:(NSMutableData*)outputt{
output = outputt;
}
-(void) setInput:(NSMutableData*)inputt{
input = inputt;
}
#end
NetworkCommunication.m
- (void) observeValueForKeyPath:(NSString*)keyPath ofObject:(id)object change:(NSDictionary*)change context:(void*)context {
//NSLog(#"changed!!!!");
if ([keyPath isEqualToString:#"output"]) {
Data *data = [Data sharedData];
[self writeOut:data.output];
}
}
- (void)writeOut:(NSString *)s {
NSString *dataTo = [NSString stringWithFormat:#"%#\n", s];
NSData *data = [[NSData alloc] initWithData:[dataTo dataUsingEncoding:NSASCIIStringEncoding]];
[outputStream write:[data bytes] maxLength:[data length]];
}
It generally creates great amount of data, which in 2,5 min was about 200 MB in virtual memory. I tried to simply pass stringWithFormat: directly to my writeOut: function however it gives nothing, not idea how to deal with it.
If someone asks why I use stringWithFormat, simply because I need to put \n for server to read the message.
Any help much appreciated.
EDIT 1:
I tied it different way. In my AudioProcessor.m (because that's the data is created - in the recorder callback) I set it this way:
dataOut = [[NSMutableData alloc] initWithCapacity:0];
[dataOut appendBytes:(const void *)intFromBuffer length:length * sizeof(SInt16)];
net = [NetworkCommunication init];
const char *s = [dataOut bytes];
[[net outputStream] write:s maxLength:strlen(s)];
Now it generates insane allocations of type Malloc 1,00KB, and Malloc 2,00 KB with NSThread callStackSymbol and NSThread callStackReturnAddresses. What's still wrong?

Answer 1

Did you try sending C strings?
const char *s = [dataTo UTF8String];
[outputStream write:s maxLength:strlen(s)];