Rancher k3s Elemental deployment RAM usage

SUSE Rancher Prime Rancher Setup Public Cloud
1

Hello,

What is the minimum RAM needed to get k3s deployed by Rancher on Elemental?
What is the difference in RAM consumption between sqlLite and Etcd?

I am new to Kubernetes and started testing to learn. Rancher provides an easy way for deployment close to monkey prove. I set-up three nodes as VM on Proxmox and deployed k3s v1.31.4 on Elemental. Each node with 8 GB RAM and additionally the Monitoring tool is installed. The nodes where idling with about 90% ram usage for a day. Then I increased the RAM to 12 GB pe node and suddenly the RAM usage dropped to about 3 GB. Now, after two more days of idling the RAM usage is at about 10 GB for each node.

Is it possible that the nodes did not properly came up with 8 GB due to RAM shortage?
I thought k3s is a light weight distribution. How much more resources are required for Etcd, Rancher is using in the deployment?

Screenshot 2025-02-11 201049
Screenshot 2025-02-11 2010491113Ă—799 47.1 KB

2

RAM usage on Linux is a bit tricky and cannot be derived from just looking a “free ram”.
The Linux storage cache layer will use memory to cache disk blocks and only drop cache entries if Linux workloads ask for memory.

The amount of RAM required to run Kubernetes entirely depends on the workload you’re running. Linux+Kubernetes will probably run with 4GB RAM but can only accomodate a small workload.
Anything more will be used by your workload(s).

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