* simulate late connection pool failures.
   */
  object DisconnectAfterRequest : SocketPolicy

  /**
   * Half close connection (InputStream for client) after reading the request but before
   * writing the response. Use this to simulate late connection pool failures.
   */
  object HalfCloseAfterRequest : SocketPolicy

   * turn, and does not create any threads of its own.
   *
   * <p>After execution begins on a thread from the {@code delegate} {@link Executor}, tasks are
   * polled and executed from a task queue until there are no more tasks. The thread will not be
   * released until there are no more tasks to run.
   *

)

// aligned sync.Pool's
var (
	ODirectPoolLarge = sync.Pool{
		New: func() interface{} {
			b := disk.AlignedBlock(LargeBlock)
			return &b
		},
	}
	ODirectPoolMedium = sync.Pool{
		New: func() interface{} {
			b := disk.AlignedBlock(MediumBlock)
			return &b
		},
	}
	ODirectPoolSmall = sync.Pool{
		New: func() interface{} {
			b := disk.AlignedBlock(SmallBlock)

	if err != nil {
		return err
	}
	setDriveCount := uint64(v)

	var pools []poolArgs
	switch cv.Version {
	case "v1":
		cfV1 := config.ServerConfigV1{}
		if err = yaml.Unmarshal(rd, &cfV1); err != nil {
			return err
		}

		pools = make([]poolArgs, 0, len(cfV1.Pools))
		for _, list := range cfV1.Pools {
			pools = append(pools, poolArgs{
				args:          list,
				setDriveCount: setDriveCount,
			})

## Version 4.2.1

_2019-10-02_

 *  Fix: In 4.1.0 we introduced a performance regression that prevented connections from being
    pooled in certain situations. We have good test coverage for connection pooling but we missed
    this because it only occurs if you have proxy configured and you share a connection pool among
    multiple `OkHttpClient` instances.

    // If we raced another call connecting to this host, coalesce the connections. This makes for
    // 3 different lookups in the connection pool!
    val pooled3 = routePlanner.planReusePooledConnection(this, routes)
    if (pooled3 != null) return pooled3.connection

    connection.withLock {
      connectionPool.put(connection)
      user.acquireConnectionNoEvents(connection)
    }

System.out.println("REQUEST 1 (new connection)");
try (Response response = client.newCall(request).execute()) {
  // Consume and discard the response body.
  response.body().source().readByteString();
}

System.out.println("REQUEST 2 (pooled connection)");
try (Response response = client.newCall(request).execute()) {
  // Consume and discard the response body.
  response.body().source().readByteString();
}
```

	for i, pool := range nmeta2.Pools {
		if i == 0 {
			nmeta2.Pools[i] = PoolStatus{
				CmdLine:    pool.CmdLine,
				ID:         i,
				LastUpdate: UTCNow(),
				Decommission: &PoolDecommissionInfo{
					Complete: false,
				},
			}
		}
	}

	testCases := []struct {
		meta           poolMeta
		pools          []*erasureSets
		expectedUpdate bool
		expectedErr    bool

    // Second call attempts the pooled connection, and it fails. Then it retries a new route which
    // succeeds.
    val response2 = client.newCall(request).execute()
    assertThat(response2.body.string()).isEqualTo("abc")
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(1) // Pooled connection.
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(0) // New connection.

Finally, we SHOULD tell our (HBONE) peers we are shutting down.
This can help ensure that clients do not hold onto pooled connections for too long.
This is not strictly required; Ztunnel clients have both keepalives (which will start to fail once the other end is shut down) and pool idle timeouts (which will close the connection when it has had no activity for some period; because the backend is gone, there will be no activity).