title: When can I not use atomic properties?
body: <p>I know there are answers on atomic vs. non-atomic answers, but they mostly seem to be fairly old (2011 and earlier), so I'm hoping for updated advice. My understanding is that non-atomic properties are faster but not thread safe. Does this mean that any property that might be accessed from multiple threads at the same time should always be atomic? Are there conditions that can make it ok to make it non-atomic? What other concerns are there in determining whether to make a property atomic or nonatomic?</p>