K3s is a lightweight Kubernetes distribution by Rancher Labs intended for IoT, Edge, and cloud deployments. With only 40MB in size, with zero-to-minimal dependencies and memory requirement of less than 512MB, K3s is the lightest Kubernetes distribution to date.
Ranked in these QuestionsQuestion Ranking
Pro Removes non-standard features
All of the non-v1 features are removed in K3s, along with vendor-specific extensions, making it smaller.
Pro Simple Install
wget -qO - https://get.k3s.io | sh - can get you a running K3s node in seconds. Want to scale? do the same part and edit the systemd unit, and you're set.
Pro No requirement for Docker
Unlike most distributions, K3s does not rely on Docker, it is optional. K3s has its own runtime packaged, which is containerd.
Pro No dependencies
K3s requires you only to run the binary, nothing more. You just need a sane kernel.
With 40MB binary size, and with 512MB memory requirement, K3s is the only distribution that has surpassed Hyperkube as the smallest distribution and surpassed all enterprise distributions in efficiency.
Pro You don't need a PhD in Kubernetes clusterology
Kubernetes architecture feels like you'd need a course for it soon, but K3s removes this strain, making it the easiest Kubernetes distribution to use.
Pro Not reliant to etcd3
K3s uses SQLite3 in place of etcd. However, you can specify etcd again if you want to use it.
Con Incompatible with Helm and Helm charts
with the removal of most non-v1 additions, most Helm charts won't work. Even Helm won't work as well.
Con Not capable of HA
At this time of writing, Rancher states that K3s is not HA-ready yet. This is bound to change soon.
Con No ingresses
Because Ingress is not a v1 feature, This is removed. You must use the LoadBalancer instead.