Rocksteady is an effort to use Esper Complex Event Processing (CEP) to analyze user defined metrics. You can use it to parse your data and turn it into events that Esper CEP can query so that you can respond to events in real time.
"Rocksteady can be used in a number of different environments, AdMob use it to determine the cause of events such as latency. We monitor requests per second (rps) and a slew of other metrics such as CPU and network traffic, then put them together in a prediction algorithm such as Holt Winters to predict a confidence band for next arriving value. We then record an event whenever metrics are outside the band more than a certain number of times in a row. This's what we call auto threshold establishment. Now, if we've a SLA we really care about, such as response time, we can set a hard threshold, say 250ms. When response time slows beyond 250ms, Rocksteady tells us whether rps, CPU or network crossed their respective thresholds. Now instead of just knowing there is a latency problem, we can also quickly pinpoint the potential cause," explains Google.
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