Key idea
The Metrics tab shows three things over time: how much CPU and memory your service uses, and how many spherelets run it. A number only means something next to its ceiling, and the ceiling is your shape.
Where it is
Open a service and choose Metrics. Web services, private services and background workers have it; cron jobs don't.
At the top, a row of three numbers: CPU, Memory and Spherelets. Each shows the latest value and how much it changed over the window. Below them, the CPU chart runs full width, with Memory and Spherelets side by side underneath.
The time range picker sets the window. It opens on Last 1 hour; the shortest is Last 5 minutes and the longest Last 90 days.
What each chart measures
- CPU, in vCPU. Each point is an average over a short stretch, so a spike of a few seconds looks lower than it was.
- Memory, in MB or GB: what the app holds right now. A line that climbs and never comes down is worth a look.
- Spherelets: how many are running. Flat at your count, except during an update, a restart or autoscaling.
Compare with the ceiling
Each spherelet is guaranteed a share of CPU, can use up to its shape's vCPU when spare CPU is available, and never more. Memory is a fixed ceiling:
| Shape | CPU ceiling | Guaranteed CPU | Memory ceiling |
|---|---|---|---|
| Flex 512 MB | 0.5 vCPU | 0.125 vCPU | 512 MB |
| Standard 1 | 1 vCPU | 0.5 vCPU | 2 GB |
| Standard 2 | 2 vCPU | 1 vCPU | 4 GB |
So 0.4 vCPU is nearly full on Flex 512 MB and light on Standard 2. Find your service's shape in Settings, under Spherelets, before you read anything into the charts.
Sum, Avg and Max
With more than one spherelet, the CPU and Memory charts combine them. The toggle on each chart picks how, and the chart's title shows the choice, such as CPU · sum or Memory · max:
- Sum (the default): the total across spherelets.
- Avg: a typical spherelet.
- Max: the busiest one.
Compare Max with one spherelet's ceiling. A sum of 0.6 vCPU across two Flex spherelets could be two at 0.3, or one pinned at 0.5 while the other barely works. Only Max tells you which.
With one spherelet all three read the same. The toggle is there for when you scale out (Module 7).
Check yourself