private static ThreadPoolExecutor createExecutor() {
        int threadCount = Runtime.getRuntime().availableProcessors();
        ThreadPoolExecutor executor = new ThreadPoolExecutor(threadCount, threadCount, 1L, TimeUnit.SECONDS,
                                                             new LinkedBlockingQueue<>(),
                                                             ThreadFactoryFactory.getThreadFactory("rendering"));
        executor.prestartAllCoreThreads();
        return executor;
    }
The stack of listeners to ancestor datalist completions above the current one
container-core/src/main/java/com/yahoo/processing/rendering/AsynchronousSectionedRenderer.java