/**
   * A means for changing an Ordering into another Ordering. Each instance is responsible for
   * creating the alternate Ordering, and providing a List that is known to be ordered, based on an
   * input List known to be ordered according to the input Ordering.
   */
  private enum OrderingMutation {
    REVERSE {
      @Override
      <T extends @Nullable Object> Scenario<?> mutate(Scenario<T> scenario) {

  /**
   * A means for changing an Ordering into another Ordering. Each instance is responsible for
   * creating the alternate Ordering, and providing a List that is known to be ordered, based on an
   * input List known to be ordered according to the input Ordering.
   */
  private enum OrderingMutation {
    REVERSE {
      @Override
      <T extends @Nullable Object> Scenario<?> mutate(Scenario<T> scenario) {

	OrigVolume string             `msg:"ov"`
	FilePath   string             `msg:"fp"`
	UpdateOpts UpdateMetadataOpts `msg:"uo"`
	FI         FileInfo           `msg:"fi"`
}

// UpdateMetadataOpts provides an optional input to indicate if xl.meta updates need to be fully synced to disk.
type UpdateMetadataOpts struct {
	NoPersistence bool `msg:"np"`
}

// CheckPartsHandlerParams are parameters for CheckPartsHandler

	buf    bytes.Buffer
}

func newExitCodeFilter(w io.Writer) (*exitCodeFilter, string) {
	const exitStr = "exitcode="

	// Build a regexp that matches any prefix of the exit string at the end of
	// the input. We do it this way to avoid assuming anything about the
	// subcommand output (e.g., it might not be \n-terminated).
	var exitReStr strings.Builder
	for i := 1; i <= len(exitStr); i++ {

		return
	}

	// Route directly to output.
	m.respWait = out
}

// RequestStream will send a single payload request and stream back results.
// 'requests' can be nil, in which case only req is sent as input.
// It will however take less resources.
func (m *muxClient) RequestStream(h HandlerID, payload []byte, requests chan []byte, responses chan Response) (*Stream, error) {
	if m.init {

接下来，它 🤖 完成第一个任务（比如是我们的"慢文件"📝) 并继续与之相关的一切。

这个"等待其他事情"通常指的是一些相对较慢（与处理器和 RAM 存储器的速度相比）的 <abbr title="Input and Output">I/O</abbr> 操作，比如说：

* 通过网络发送来自客户端的数据
* 客户端接收来自网络中的数据
* 磁盘中要由系统读取并提供给程序的文件的内容
* 程序提供给系统的要写入磁盘的内容
* 一个 API 的远程调用
* 一个数据库操作，直到完成
* 一个数据库查询，直到返回结果
* 等等.

这个执行的时间大多是在等待 <abbr title="Input and Output">I/O</abbr> 操作，因此它们被叫做 "I/O 密集型" 操作。

}

// Maximum 4KiB size per object retention config.
const maxObjectRetentionSize = 1 << 12

// ParseObjectRetention constructs ObjectRetention struct from xml input
func ParseObjectRetention(reader io.Reader) (*ObjectRetention, error) {
	ret := ObjectRetention{}
	if err := xml.NewDecoder(io.LimitReader(reader, maxObjectRetentionSize)).Decode(&ret); err != nil {
		return nil, err
	}

   * {@code '-'} (<code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Float#parseFloat(String)}, this method returns {@code null} instead of
   * throwing an exception if parsing fails. Valid inputs are exactly those accepted by {@link
   * Float#valueOf(String)}, except that leading and trailing whitespace is not permitted.
   *
   * <p>This implementation is likely to be faster than {@code Float.parseFloat} if many failures

   * {@code '-'} (<code>'&#92;u002D'</code>) is recognized as the minus sign.
   *
   * <p>Unlike {@link Float#parseFloat(String)}, this method returns {@code null} instead of
   * throwing an exception if parsing fails. Valid inputs are exactly those accepted by {@link
   * Float#valueOf(String)}, except that leading and trailing whitespace is not permitted.
   *
   * <p>This implementation is likely to be faster than {@code Float.parseFloat} if many failures

      int expectedSize) {
    return new CompactHashSet<>(expectedSize);
  }

  /**
   * Maximum allowed false positive probability of detecting a hash flooding attack given random
   * input.
   */
  @VisibleForTesting(
      )
  static final double HASH_FLOODING_FPP = 0.001;

  /**
   * Maximum allowed length of a hash table bucket before falling back to a j.u.LinkedHashSet based