Question about ScheduledExecutorService.shceduleAtFixedRate - I schedule taskA to run every 500 millis, which blocks for 1000 millis. Now subsequent executions aren't gonna wait the extra 500 millis, but rather commence immediately after the previous one.
taskA acquires an intrinsic lock, which is also (attempted) acquired by a different thread. Since intrinsic locks have no fairness guarantees this thread is running a risk of starvation, so here's my question: Is there a good/clean way to avoid this risk? E.g. schedule the task to run every 1500 millis (doesn't sound very waterproof)? Or do we expect the lock acquisition to exhibit a kind of "amortized fairness"?
Yes, you can use scheduleWithFixedDelay:
Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next. If any execution of the task encounters an exception, subsequent executions are suppressed. Otherwise, the task will only terminate via cancellation or termination of the executor.
So the delay you give is the time between end of last end start of next - ie no overlap between runs.