Understanding your CPU and memory usage can help when making decisions about build optimization. Each build on CircleCI will be allocated specific vCPUs and memory, based on the executor type selected.
Docker Executor Usage Statistics
For builds using the Docker executor we have provided a Resources tab on the "Job Details" page as well as a path through the Insights tab on the left of the page. This allows developers to understand the CPU and memory utilization profile of their Docker executor builds, especially if they are under-provisioned (or over-provisioned for that matter).
Note: For Docker-executor jobs that use multiple images, note that this graph accounts for all of the containers, not just the primary container. In addition, the data points are captured at 15-seconds intervals, so if your job completes before 15 seconds, there would be no data points on the graph then.
You can then provision a larger resource class to allocate resources accordingly.