Hi, JVM.CPU.Load is just a wrapper (MetricUtils.instantiateCPUMetrics) on top of OperatingSystemMXBean.getProcessCpuLoad (see https://docs.oracle.com/javase/7/docs/jre/api/management/extension/com/sun/management/OperatingSystemMXBean.html#getProcessCpuLoad())
Usually it looks weird if you have multiple CPU cores. For example, if you have a job with a single slot 100% utilizing a single CPU core on a 8 core machine, the JVM.CPU.Load will be 1.0/8.0 = 0.125. It's also a point-in-time snapshot of current CPU usage, so if you're collecting your metrics every minute, and the job has spiky workload within this minute (like it's idle almost always and once in a minute it consumes 100% CPU for one second), so you have a chance to completely miss this from the metrics. As for me personally, JVM.CPU.Time is more clear indicator of CPU usage, which is always increasing amount of milliseconds CPU spent executing your code. And it will also catch CPU usage spikes. Roman Grebennikov | g...@dfdx.me On Mon, Aug 3, 2020, at 23:34, Bajaj, Abhinav wrote: > Hi, > > I am trying to understand the CPU Load metrics reported by Flink 1.7.1 > running with openjdk 1.8.0_212 on K8s. > > After deploying the Flink Job on K8s, I tried to get CPU Load metrics > following this documentation > <https://ci.apache.org/projects/flink/flink-docs-release-1.7/monitoring/metrics.html#rest-api-integration>. > curl > localhost:8081/taskmanagers/7737ac33b311ea0a696422680711597b/metrics?get=Status.JVM.CPU.Load,Status.JVM.CPU.Time > [{"id":"Status.JVM.CPU.Load","value":"0.0023815194093831865"},{"id":"Status.JVM.CPU.Time","value":"23260000000"}] > > The value of the CPU load looks odd to me. > > What is the unit and scale of this value? > How does Flink determine this value? > > Appreciate your time and help here. > ~ Abhinav Bajaj >
