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Apache spark Spark中的水印是如何工作的?_Apache Spark - Fatal编程技术网

Apache spark Spark中的水印是如何工作的?

Apache spark Spark中的水印是如何工作的?,apache-spark,Apache Spark,我在理解水印、浏览官方文件时感到困惑 这里是图片 https://spark.apache.org/docs/latest/img/structured-streaming-watermark-update-mode.png 医生说: the engine will maintain state and allow late data to update the state until (max event time seen by the engine - late threshold &

我在理解水印、浏览官方文件时感到困惑

这里是图片

https://spark.apache.org/docs/latest/img/structured-streaming-watermark-update-mode.png
医生说:

 the engine will maintain state and allow late data to update the state until (max event time seen by the engine - late threshold > T)
所以,如果我们看到图像中的水印,在12:15计算的是
12:04
。为什么这12:04与发动机看到的
最大事件时间-延迟阈值>T
有关?哪个窗口(T)的值更大