我们观察到 iOS 10.2 中的崩溃峰值（_dispatch_call_block_and_release 中的 libdispatch.dylib）。这种崩溃并不是什么新鲜事，然而，自 iOS 10.2 发布以来出现了一次峰值。有没有人经历过同样的崩溃并找到了根本原因？谢谢！
libobjc.A.dylib in objc_msgSend + 16
libdispatch.dylib in _dispatch_call_block_and_release + 20
libdispatch.dylib in _dispatch_client_callout + 12
libdispatch.dylib in _dispatch_queue_serial_drain + 924
libdispatch.dylib in _dispatch_queue_invoke + 648
libdispatch.dylib in _dispatch_queue_override_invoke + 356
libdispatch.dylib in _dispatch_root_queue_drain + 568
libdispatch.dylib in _dispatch_worker_thread3 + 120
libsystem_pthread.dylib in _pthread_wqthread + 1284
libsystem_pthread.dylib in start_wqthread + 0