# Release 2.12.1

### Bug Fixes and Other Changes

<div style="text-align: right; margin-right: 10%;">Kevin Glisson, Marc Vilanova, Forest Monsen - <strong>Netflix</strong> <a href="https://netflixtechblog.com/introducing-dispatch-da4b8a2a8072" target="_blank"><small>(ref)</small></a></div>

---

"_Tôi vô cùng hào hứng về **FastAPI**. Nó rất thú vị_"

    // At 0ms the server sends 3 unexpected pongs. The client accepts 'em and ignores em.
    server.webSocket!!.pong("pong 1".encodeUtf8())
    client.processNextFrame()
    server.webSocket!!.pong("pong 2".encodeUtf8())
    client.processNextFrame()
    taskFaker.runTasks()
    server.webSocket!!.pong("pong 3".encodeUtf8())
    client.processNextFrame()

    @Override
    public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException {
      long nanos = unit.toNanos(timeout);
      synchronized (lock) {
        while (true) {
          if (shutdown && runningTasks == 0) {
            return true;
          } else if (nanos <= 0) {
            return false;
          } else {
            long now = System.nanoTime();

 *  Fix: Don't leak file handles when a cache disk write fails.

 *  Fix: Don't hang when the public suffix database cannot be loaded. We had a bug where a failure
    reading the public suffix database would cause subsequent reads to hang when they should have
    crashed.

 *  Fix: Avoid `InetAddress.getCanonicalHostName()` in MockWebServer. This avoids problems if the

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!!! tip

) {
  /** The total number of bytes consumed. */
  var total: Long = 0L
    private set

  /** The total number of bytes acknowledged by outgoing `WINDOW_UPDATE` frames. */
  var acknowledged: Long = 0L
    private set

  val unacknowledged: Long
    @Synchronized get() = total - acknowledged

  @Synchronized
  fun update(
    total: Long = 0,
    acknowledged: Long = 0,
  ) {
    check(total >= 0)

     * Connections will still be closed if they idle beyond the keep-alive but will be replaced.
     */
    @JvmField val minimumConcurrentCalls: Int = 0,
    /** How long to wait to retry pre-emptive connection attempts that fail. */
    @JvmField val backoffDelayMillis: Long = 60 * 1000,
    /** How much jitter to introduce in connection retry backoff delays */
    @JvmField val backoffJitterMillis: Int = 100,
  )

   */
  private val maxIdleConnections: Int,
  keepAliveDuration: Long,
  timeUnit: TimeUnit,
  internal val connectionListener: ConnectionListener,
  private val exchangeFinderFactory: (RealConnectionPool, Address, ConnectionUser) -> ExchangeFinder,
) {
  internal val keepAliveDurationNs: Long = timeUnit.toNanos(keepAliveDuration)

  @Volatile

        nextOutFrame = outFramesIterator.next()
      }

      if (nextOutFrame != null && nextOutFrame.sequence == i) {
        val start = nextOutFrame.start
        var truncated: Boolean
        var end: Long
        if (outFramesIterator.hasNext()) {
          nextOutFrame = outFramesIterator.next()
          end = nextOutFrame.start
          truncated = false
        } else {
          end = outBytes.size.toLong()