How does virtual threads (Project Loom) impact performance or memory usage?

Virtual threads, introduced in Project Loom, bring a significant impact on performance and memory usage in Java applications. By allowing developers to create lightweight, user-mode threads, virtual threads provide a mechanism for handling high concurrency with less overhead compared to traditional threads.

One of the main advantages of virtual threads is their ability to manage thousands of concurrent tasks without the burden of a thread-per-request model typically seen in conventional Java programming. This can lead to reduced memory footprint, as each virtual thread consumes far less memory than a traditional platform thread.

Additionally, the scheduling of virtual threads is managed by the Java Virtual Machine (JVM), allowing for better resource utilization and improved responsiveness, particularly in I/O-bound applications. This means that developers can focus more on writing straightforward, sequential code, which is easier to read and maintain, instead of dealing with complex callback patterns found in asynchronous programming.