/** Returns the number of idle connections in the pool. */
  fun idleConnectionCount(): Int = delegate.idleConnectionCount()

  /** Returns total number of connections in the pool. */
  fun connectionCount(): Int = delegate.connectionCount()

  internal val connectionListener: ConnectionListener
    get() = delegate.connectionListener

  /** Close and remove all idle connections in the pool. */
  fun evictAll() {

    if (http2Connection != null) {
      return http2Connection.isHealthy(nowNs)
    }

    val idleDurationNs = lock.withLock { nowNs - idleAtNs }
    if (idleDurationNs >= IDLE_CONNECTION_HEALTHY_NS && doExtensiveChecks) {
      return socket.isHealthy(source)
    }

    return true
  }

  /** Refuse incoming streams. */
  @Throws(IOException::class)

      if (!inputExhausted) {
        responseBodyComplete()
      }
      closed = true
    }
  }

  companion object {
    private const val NO_CHUNK_YET = -1L

    private const val STATE_IDLE = 0 // Idle connections are ready to write request headers.
    private const val STATE_OPEN_REQUEST_BODY = 1
    private const val STATE_WRITING_REQUEST_BODY = 2
    private const val STATE_READ_RESPONSE_HEADERS = 3

          return -1L
        }
      },
      delayNanos,
    )
  }

  /** Returns a latch that reaches 0 when the queue is next idle. */
  fun idleLatch(): CountDownLatch {
    taskRunner.lock.withLock {
      // If the queue is already idle, that's easy.
      if (activeTask == null && futureTasks.isEmpty()) {
        return CountDownLatch(0)
      }

Blocking APIs may be inefficient because you hold a thread idle while waiting on the network. Threads are expensive because they have both a memory overhead and a context-switching overhead.

#### Framed protocols

  }

  @Test
  fun idleCallbackInvokedWhenIdle() {
    val idle = AtomicBoolean()
    dispatcher.idleCallback = Runnable { idle.set(true) }
    client.newCall(newRequest("http://a/1")).enqueue(callback)
    client.newCall(newRequest("http://a/2")).enqueue(callback)
    executor.finishJob("http://a/1")
    assertThat(idle.get()).isFalse()
    val ready = CountDownLatch(1)
    val proceed = CountDownLatch(1)

    // Connections are replaced if they idle out or are evicted from the pool
    evictAllConnections(pool)
    assertThat(pool.connectionCount()).isEqualTo(2)
    forceConnectionsToExpire(pool, expireTime)
    assertThat(pool.connectionCount()).isEqualTo(2)

    // Excess connections aren't removed until they idle out, even if no longer needed

 * thread, which yields its execution privilege while calling [runTasks], [runNextTask], or
 * [advanceUntil]. These functions don't return until the task threads are all idle.
 *
 * Task threads release their execution privilege in these ways:
 *
 *  * By yielding in [TaskRunner.Backend.coordinatorWait].
 *  * By yielding in [BlockingQueue.poll].
 *  * By completing.
 */

    be called.

    Web sockets have always been had pings, but pings on HTTP/2 connections is
    new in this release. Pings are used for connections that are busy carrying
    calls and for idle connections in the connection pool. (Pings do not impact
    when pooled connections are evicted).

    If you have a configured ping interval, you should confirm that it is long

    }

  /**
   * A callback to be invoked each time the dispatcher becomes idle (when the number of running
   * calls returns to zero).
   *
   * Note: The time at which a [call][Call] is considered idle is different depending on whether it
   * was run [asynchronously][Call.enqueue] or [synchronously][Call.execute]. Asynchronous calls
   * become idle after the [onResponse][Callback.onResponse] or [onFailure][Callback.onFailure]