<p>Is it worth using SSD as boot disk? I'm not planning to access local disks <a href="https://cloud.google.com/container-engine/docs/local-ssd" rel="nofollow noreferrer">within pods</a>.</p>

<p>Also, GCP by default creates 100GB disk. If I use 20GB disk, will it cripple the cluster or it's OK to use smaller sized disks?</p>

<p>Why one or the other?. Kubernetes (Google Conainer Engine) is mainly Memory and CPU intensive unless your applications need a huge throughput on the hard drives. If you want to save money you can create tags on the nodes with HDD and use the node-affinity to tweak which pods goes where so you can have few nodes with SSD and target them with the affinity tags.</p>
