What parallelism mechanisms should be used for bulk insert? Where will the ExecutorService get tasks from?

For bulk insert in parallel mode in Java, ExecutorService is often used. It is an interface for managing a thread pool, which allows executing tasks asynchronously.

Working mechanism:

• A thread pool is created, for example, Executors.newFixedThreadPool(n).
• Tasks (such as inserting data chunks) are created as Runnable or Callable objects.
• These tasks are submitted to the ExecutorService via submit() or execute() methods.

Where does the ExecutorService get the tasks from?

• Tasks are placed in an internal task queue when submit() is called.
• Threads from the pool take tasks from this queue and execute them.

Example:

ExecutorService executor = Executors.newFixedThreadPool(4);

for (List<Data> chunk : dataChunks) {
    executor.submit(() -> {
        // bulk insert chunk
    });
}

executor.shutdown();
executor.awaitTermination(1, TimeUnit.HOURS);

Thus, ExecutorService manages the task queue and thread pool, ensuring parallel execution of bulk insert.