CPU execution time graph
I want to understand the CPU time usage for my worker, so I looked at a specific deployed version's CPU usage stats. But in this image, I see 3 different numbers for the median CPU time - 210.8ms, 10,973.9 ms, and 5.8ms. Which one is correct? Am I misreading the data?
3 Replies
They're all correct. The graph shows percentile CPU time. https://en.wikipedia.org/wiki/Percentile
Percentile
In statistics, a k-th percentile, also known as percentile score or centile, is a score below which a given percentage k of scores in its frequency distribution falls ("exclusive" definition) or a score at or below which a given percentage falls ("inclusive" definition).
Percentiles are expressed in the same unit of measurement as the input sco...
CPU time is a range and not all requests have the same CPU time. In your case, the median time is 200ms but the the 99th percentile was 12k ms
Median
The median of a set of numbers is the value separating the higher half from the lower half of a data sample, a population, or a probability distribution. For a data set, it may be thought of as the “middle" value. The basic feature of the median in describing data compared to the mean (often simply described as the "average") is that it is not s...
What is the 50th percentile 10,973.9ms at the top referring to? I thought that and the 210.8ms on the left would be the same, but they're different
The 50th percentile number at the bottom of the white rectangle shows 5.8ms too, different from the rest