Syscall_thread_switch iOS 8.3 race - CocoaLumberjack bug? how to debug this?

Question

I use the race condition in my application where all or all but 1 thread get stuck in syscall_thread_switch whenever I pause debugging. It plays much more often on a simulator, but also on an iPad Air. There is ALWAYS at least 2 threads stuck in CocoaLumberjack queueLogMessage: - see screenshots.

I have never seen this before in 8.1 and 8.2, but I often click it on 8.3. I am not saying that this is a 8.3 error :)

This is a level of difficulty that I never had to debug, so I'm not sure what to do. I hope I have provided sufficient information, please let me know if you need more (please specify how to get the information if it is not dead). Could you help me debug this ?! Millions of thanks.

Answer 1

I ran into a similar issue with NSOperations in NSOperationQueue in iOS 8.3 (not related to CocoaLumberjack). I had parallel operations creating my own threads that are no longer needed. He felt great in 8.2, but not 8.3.

In the startup method, I simply replaced:

[NSThread detachNewThreadSelector:@selector(main) toTarget:self withObject:nil]; 

FROM

 [self main];