## 协程

**协程**只是 `async def` 函数返回的一个非常奇特的东西的称呼。Python 知道它有点像一个函数，它可以启动，也会在某个时刻结束，而且它可能会在内部暂停 ⏸ ，只要内部有一个 `await`。

通过使用 `async` 和 `await` 的异步代码的所有功能大多数被概括为"协程"。它可以与 Go 的主要关键特性 "Goroutines" 相媲美。

## 结论

让我们再来回顾下上文所说的：

> Python 的现代版本可以通过使用 `async` 和 `await` 语法创建**协程**，并用于支持**异步代码**。

现在应该能明白其含义了。✨

所有这些使得 FastAPI（通过 Starlette）如此强大，也是它拥有如此令人印象深刻的性能的原因。

## 非常技术性的细节

	go func() {
		select {
		case <-cc:
			return
		case <-c:
			buf := make([]byte, 1<<20)
			stacklen := runtime.Stack(buf, true)
			fmt.Printf("=== Timeout, assuming deadlock ===\n*** goroutine dump...\n%s\n*** end\n", string(buf[:stacklen]))
			os.Exit(2)
		}
	}()
	return func() {
		close(cc)
	}

	go func() {
		select {
		case <-cc:
			return
		case <-c:
			buf := make([]byte, 1<<20)
			stacklen := runtime.Stack(buf, true)
			fmt.Printf("=== Timeout, assuming deadlock ===\n*** goroutine dump...\n%s\n*** end\n", string(buf[:stacklen]))
			os.Exit(2)
		}
	}()
	return func() {
		close(cc)
	}
}

func assertNoActive(t *testing.T, c *Connection) {
	t.Helper()

				globalLocalSetDrives[endpoint.PoolIdx][endpoint.SetIdx][endpoint.DiskIdx] = storage
				return true
			}

			if createStorage(endpoint) {
				continue
			}

			// Start async goroutine to create storage.
			go func(endpoint Endpoint) {
				for {
					time.Sleep(3 * time.Second)
					if createStorage(endpoint) {
						return
					}
				}
			}(endpoint)

		}
	}

	if err != nil {
		decomLogIf(ctx, fmt.Errorf("invalid workers value err: %v, defaulting to %d", err, len(pool.sets)))
		workerSize = len(pool.sets)
	}

	// Each decom worker needs one List() goroutine/worker
	// add that many extra workers.
	workerSize += len(pool.sets)

	wk, err := workers.New(workerSize)
	if err != nil {
		return err
	}

	var vc *versioning.Versioning

		g.Go(func() error {
			// Get the set where it would be placed.
			storageInfos[index] = getDiskInfos(ctx, pool.getHashedSet(object).getDisks()...)
			return nil
		}, index)
	}

	// Wait for the go routines.
	g.Wait()

	for i, zinfo := range storageInfos {
		if zinfo == nil {
			serverPools[i] = poolAvailableSpace{Index: i}
			continue
		}
		var available uint64
		if !isMinioMetaBucketName(bucket) {

			return nil
		})
	})

	readDirFn(pathJoin(drivePath, minioMetaTmpBucket), func(tmpDir string, typ os.FileMode) error {
		if strings.HasPrefix(tmpDir, ".trash") {
			// do not remove .trash/ here, it has its own routines
			return nil
		}
		vi, err := disk.StatVol(ctx, pathJoin(minioMetaTmpBucket, tmpDir))
		if err != nil {
			return nil
		}
		w := xioutil.NewDeadlineWorker(globalDriveConfig.GetMaxTimeout())

* Version-guard Kubectl client Guestbook application test against deployments ([#24478](https://github.com/kubernetes/kubernetes/pull/24478), [@ihmccreery](https://github.com/ihmccreery))
* Fix goroutine leak in ssh-tunnel healthcheck. ([#24487](https://github.com/kubernetes/kubernetes/pull/24487), [@cjcullen](https://github.com/cjcullen))

  void setBits(BitSet table) {
    for (int c = Character.MAX_VALUE; c >= Character.MIN_VALUE; c--) {
      if (matches((char) c)) {
        table.set(c);
      }
    }
  }

  // Text processing routines

  /**
   * Returns {@code true} if a character sequence contains at least one matching BMP character.
   * Equivalent to {@code !matchesNoneOf(sequence)}.
   *

	defer func() {
		if rec := recover(); rec != nil {
			gridLogIf(ctx, fmt.Errorf("handleMessages: panic recovered: %v", rec))
			debug.PrintStack()
		}
		if debugPrint {
			fmt.Println("handleMessages: write goroutine exited")
		}
		cancel(ErrDisconnected)
		c.connChange.L.Lock()
		if atomic.CompareAndSwapUint32((*uint32)(&c.state), StateConnected, StateConnectionError) {
			c.connChange.Broadcast()
		}