WatchService on MacOS is still implemented by the generic PollingWatchService, which continuously re-scans the directory consuming CPU, introduces large latencies to the generated WatchEvent's, and misses changes that occur faster than the re-scan interval. At the same time, there are two technologies available on the platform to receive the necessary information from the OS similar to what is available on Windows and Linux: Kernel Queues and File System Events, the latter being more suitable for implementing the WatchServie functionality.