Spark Streaming Processing Time vs Total Delay vs Processing Delay
<p>I am trying to understand what the different metrics that Spark Streaming outputs mean and I am slightly confused what is the difference between the <strong>Processing Time</strong>, <strong>Total Delay</strong> and <strong>Processing Delay</strong> of the last batch ? </p>

<p>I have looked at the Spark Streaming guide which mentions the <strong>Processing Time</strong> as a key metric for figuring if the system is falling behind, but other places such as "<em>Pro Spark Streaming: The Zen of Real-Time Analytics Using Apache Spark</em>" speak about using <strong>Total Delay</strong> and <strong>Processing Delay</strong>. I have failed to find any documentation that lists all the metrics produced by Spark Streaming with explanation what each one of them means. </p>

<p>I would appreciate if someone can outline what each of these three metrics means or point me to any resources that can help me understand that. </p>