href = a.get("href", "")
Show current egress rules，推荐阅读爱思助手下载最新版本获取更多信息
Wait: block until space becomes available。业内人士推荐safew官方版本下载作为进阶阅读
This overhead is mandated by the spec's reliance on promises for buffer management, completion, and backpressure signals. While some of it is implementation-specific, much of it is unavoidable if you're following the spec as written. For high-frequency streaming — video frames, network packets, real-time data — this overhead is significant.