TransformStream creates a readable/writable pair with processing logic in between. The transform() function executes on write, not on read. Processing of the transform happens eagerly as data arrives, regardless of whether any consumer is ready. This causes unnecessary work when consumers are slow, and the backpressure signaling between the two sides has gaps that can cause unbounded buffering under load. The expectation in the spec is that the producer of the data being transformed is paying attention to the writer.ready signal on the writable side of the transform but quite often producers just simply ignore it.
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"All the bigger artists seem to go for London," Elise said.
We benchmarked native WebStream pipeThrough at 630 MB/s for 1KB chunks. Node.js pipeline() with the same passthrough transform: ~7,900 MB/s. That is a 12x gap, and the difference is almost entirely Promise and object allocation overhead."，更多细节参见爱思助手下载最新版本