for (int i = 0; i < numThreads; i++) {
      threads[i] =
          new Thread() {
            @Override
            public void run() {
              assertSame(Boolean.TRUE, memoizedSupplier.get());
            }
          };
    }
    for (Thread t : threads) {
      t.start();
    }
    for (Thread t : threads) {
      t.join();
    }

    if (thrown.get() != null) {

    /**
     * Interval in milliseconds between crawler thread executions.
     * Used to control the rate at which new crawler threads are started
     * and the frequency of status checks.
     */
    protected long crawlingExecutionInterval = Constants.DEFAULT_CRAWLING_EXECUTION_INTERVAL;

    /**
     * Thread priority for crawler threads.
     * Defaults to normal thread priority.
     */

                    }
                }
            });
        }

        // Start all threads
        for (Thread thread : threads) {
            thread.start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // Verify results
        assertTrue(exceptions.isEmpty());

  /**
   * When we need a new thread to run tasks, we call [Backend.execute]. A few microseconds later we
   * expect a newly-started thread to call [Runnable.run]. We shouldn't request new threads until
   * the already-requested ones are in service, otherwise we might create more threads than we need.
   *
   * We use [executeCallCount] and [runCallCount] to defend against starting more threads than we

#### Do-stuff-later pool

Sometimes there's an action required like calling the application layer or responding to a ping, and the thread discovering the action is not the thread that should do the work. We enqueue a runnable on this executor and it gets handled by one of the executor's threads.

### Locks

            });
        }

        for (Thread th : threads) {
            th.start();
        }
        for (Thread th : threads) {
            th.join();
        }
        assertEquals(num, count.get());
        assertEquals(num, valueSet.size());

        Set<String> valueSet2 = Collections.synchronizedSet(new HashSet<>());
        threads = new Thread[threadNum];

     *
     * @return the {@link CrawlerContext} for the current thread, or {@code null} if no context is set.
     */
    public static CrawlerContext getCrawlerContext() {
        return ROBOT_CONTEXT_THREAD_LOCAL.get();
    }

    /**
     * Sets the current {@link CrawlerContext} for the current thread.
     * If the provided {@code crawlerContext} is {@code null}, the context is removed from the thread-local storage.

    service.setPort(9200);
});
```

## Performance Tuning

### Thread Configuration

```java
// Optimize thread pool settings
crawler.crawlerContext.setNumOfThread(20);           // Number of crawler threads
crawler.crawlerContext.setMaxThreadCheckCount(50);   // Thread monitoring frequency
```

### Connection Pool Tuning

```java

    void testConcurrentAccess() throws InterruptedException {
        // Test thread safety of getInstance
        LogStream.setInstance(testStream);

        final LogStream[] instances = new LogStream[10];
        Thread[] threads = new Thread[10];

        for (int i = 0; i < threads.length; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                instances[index] = LogStream.getInstance();

    }

    @Test
    public void testThreadSafety() throws InterruptedException {
        // Test concurrent updates from multiple threads
        Thread[] threads = new Thread[10];

        for (int i = 0; i < threads.length; i++) {
            final int index = i;
            threads[i] = new Thread(() -> {
                for (int j = 0; j < 100; j++) {
                    String name = "file" + index + "_" + j + ".txt";