title: Are increment/decrement operations are thread-safe in nodejs?
body: <p>I have simple api, to which a user can send some data. The data is JSON array of objects. My goal is to know, how many objects are currently being processed by the api. I created a global counter, and for each request I receive I add the number of objects to that counter, and when I'm done with processing the object I deduct the number from the counter. My question, is this approach thread-safe? Meaning, can I have two requests - one which just finished being processed so a deduction happens, and another new request where I add the number of requests to the counter, sort of race condition?</p>