AFNetworking Error Domain=NSPOSIXErrorDomain Code=12 "The operation couldn’t be completed. Cannot allocate memory

Question

I'm sending a lot of image files via AfNetworking to a Rails server. On edge and sometimes 3G I get this error: Error Domain=NSPOSIXErrorDomain Code=12 "The operation couldn’t be completed. Cannot allocate memory".

This is the code I'm using to send the files: https://gist.github.com/cc5482059ae3023bdf50

Is there a way to fix this?

Online some people suggest that a workaround would be to stream the files. I haven't been able to find a tutorial about streaming multiple files using AFNetworking. How can I do this?

Answer 1

How big are the images? And how many are you trying to send?

I can't seem to find an easy way to implement an NSInputStream using AFNetworking, but there's definitely one thing you should try, which is avoiding putting big objects in the autorelease pool. When you are creating big NSData instances insinde a for loop, and those are going to the autorelease pool, all that memory sticks around for as long as the loop lasts. This is one way to optimize it:

for (int i=0; i<[self.sImages count]; i++) {
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    NSData *imageData = UIImageJPEGRepresentation([self.sImages objectAtIndex:i], 0.7);
    [formData appendPartWithFileData:imageData name:@"pics[]" fileName:@"avatar.jpg" mimeType:@"image/jpeg"];
    pool drain];
}

Or, if you're using LLVM3:

for (int i=0; i<[self.sImages count]; i++) {
    @autoreleasepool {
        NSData *imageData = UIImageJPEGRepresentation([self.sImages objectAtIndex:i], 0.7);
        [formData appendPartWithFileData:imageData name:@"pics[]" fileName:@"avatar.jpg" mimeType:@"image/jpeg"];
    }
}

Answer 2

I know it's been a while since this question was asked but I just have to give my two cents on the matter.

After spending the better part of the week trying to figure this stuff out here's where I'm at right now:

• This issue happens to me on a slightly banged up old iPhone 4 running iOS 5.1.1
• Can't seem to reproduce it on a not banged up iPhone 4S running the same iOS 5.1.1

Might be because of faulty networking by the phone hardware itself or might be about the need to throttle the bandwidth (or just a bug in NSURLConnection):

http://aws.amazon.com/articles/0006282245644577

https://forums.dropbox.com/topic.php?id=25351

POSIX error 12 ("Cannot allocate memory") while uploading files from an iPhone

I would have moved to ASIHTTPRequest but it is no longer maintained, so it's now worth implementing. Maybe I should still try AFNetworking, but I'm really starting to think this is an issue which has been fixed in the iOS already (or may be a shoddy iPhone in my case).

But I cannot for the life of me find a simple explanation for this.