long d = ns - (System.nanoTime() - startTime);
      if (d > 0L) {
        millis = d / (1000 * 1000);
      } else {
        break;
      }
    }
  }

  /** Waits out termination of a thread pool or fails doing so. */
  final void joinPool(ExecutorService exec) throws InterruptedException {
    try {
      exec.shutdown();
      assertTrue(
          "ExecutorService did not terminate in a timely manner",

 *  New: `ConnectionPool.setPolicy()` configures a minimum connection pool size for a target
    address. Use this to proactively open HTTP connections.

    Connections opened to fulfill this policy are subject to the connection pool's
    `keepAliveDuration` but do not count against the pool-wide `maxIdleConnections` limit.

    void execute() {
      synchronized (runnables) {
        if (executed) {
          return;
        }
        executed = true;
      }

      while (!runnables.isEmpty()) {
        runnables.poll().execute();
      }
    }

    private static class RunnableExecutorPair {
      final Runnable runnable;
      final Executor executor;

      RunnableExecutorPair(Runnable runnable, Executor executor) {

        clearValueReferenceQueue();
      }
    }

    void clearKeyReferenceQueue() {
      while (keyReferenceQueue.poll() != null) {}
    }

    void clearValueReferenceQueue() {
      while (valueReferenceQueue.poll() != null) {}
    }

    // recency queue, shared by expiration and eviction

    /**

     * not in {@link #nextElements}, this method throws an {@link UnknownElementException}.
     *
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to

            }
        }
    }

    static MyToken getNextUniqueToken(final PriorityQueue<MyToken> que, final MyToken prev) {
        while (true) {
            final MyToken token = que.poll();
            if (token == null) {
                return null;
            }
            if (prev == null || !prev.identical(token)) {
                return token;
            }
        }
    }

    -   Uses `pycpp.sh`, `code_check_changed_files.sh`

These "env" files match up with an environment matrix that roughly covers:

-   Different Python versions
-   Linux, MacOS, and Windows machines (these pool definitions are internal)
-   x86 and arm64
-   CPU-only, or with NVIDIA CUDA support (Linux only), or with TPUs

## How to Test Your Changes to TensorFlow

You may check how your changes will affect TensorFlow by:

  }

  private static <K, V> void assertNotificationEnqueued(LocalCache<K, V> map, K key, V value) {
    RemovalNotification<K, V> notification = map.removalNotificationQueue.poll();
    assertThat(notification.getKey()).isSameInstanceAs(key);
    assertThat(notification.getValue()).isSameInstanceAs(value);
  }

  // Segment eviction tests

  }

  private static <K, V> void assertNotificationEnqueued(LocalCache<K, V> map, K key, V value) {
    RemovalNotification<K, V> notification = map.removalNotificationQueue.poll();
    assertThat(notification.getKey()).isSameInstanceAs(key);
    assertThat(notification.getValue()).isSameInstanceAs(value);
  }

  // Segment eviction tests

        ).build()
    assertThat(client.retryOnConnectionFailure).isTrue()
    executeSynchronously("/").assertBody("seed connection pool")
    executeSynchronously("/").assertBody("retry success")

    // The call that seeds the connection pool.
    eventRecorder.removeUpToEvent(CallEnd::class.java)

    // The ResponseFailed event is not necessarily fatal!