> For the complete documentation index, see [llms.txt](https://amartyushov.gitbook.io/tech/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://amartyushov.gitbook.io/tech/platforms/kubernetes/pod/resources.md).
# Resources
## Pod CPU resources
[Great article based on which below info is created](https://medium.com/@jettycloud/making-sense-of-kubernetes-cpu-requests-and-limits-390bbb5b7c92). Find inside:
* explanation of CPU resource and limits for k8s Pod
* Prometheus queries to monitor Pod metrics
```
apiVersion: v1
kind: Pod
metadata:
name: my-app
spec:
containers:
- name: app
image: my.private.registry/my-app
resources:
requests: // we are talking about it
memory: "64M"
cpu: "250m"
limits:
memory: "128M"
cpu: "500m"
```
1 CPU Unit = 1024 CPU Shares
Below is how CFS will balance PODs with different CPU Unit resource configuration among cores
{% hint style="warning" %}
A **CPU requests unit** can be understood as the **percentage of a given CPU period** that is guaranteed to Pod.
{% endhint %}
{% hint style="info" %}
a 750m CPU for a period of 100 ms means that a POD is guaranteed to have 75 ms of CPU time each 100 ms (on one or multiple cores). A 5000m CPU for a period of 1s means that a Pod is guaranteed to have 5s of CPU each 1s (1s on each of 5 cores).
{% endhint %}
It does not mean that if POD uses less resources than it requested, the CPU will remain idle. If another Pod is runnable at that time, CFS will schedule that Pod.
**CPU limit** unit can be understood as the **percentage** of each scheduler CPU period (100 ms) that a Pod cannot exceed. E.g.: ***limit of 750 m CPU means that each 100 ms period POD cannot use more than 75 ms of CPU time***.
**When an application attempts to use more CPU than it is limited to — CFS will throttle it.**
