Spot management

Spot management reschedules interrupted pods before node termination, allowing automatic and safe migration of more workloads from On-Demand to Spot instances with no risk of service disruption.

The following figure shows an example of how Spot management launches a hibernated node much faster than the current boot time:

The magic behind the scenes

When you activate Spot management on a workload, the following automatic steps ensure protection:

1. Kompass ensures that the  workload and Karpenter configurations enable using Spot nodes, modifying configurations if necessary.

2. Hibernated nodes start warming up.
   For more information about hibernated nodes, see HiberScale technology.

3. Interruption protection begins immediately for all pods from protected workloads hosted on Spot instance nodes.

   1. When AWS notifies about a Spot interruption, Kompass reactivates pre-baked hibernated nodes to replace the interrupted nodes.

   2. At the same time, Karpenter evicts the pods being served by the current node and launches a new node. Pods are evicted according to the limits in the PDB.

      Evicted pods are returned to the unscheduled pods pool, where they will be served by the reactivated node as soon as it is ready.

   3. When the Karpenter node is able to serve requests, the reactivated node is gradually drained and returned to hibernation. All pods are now served by the Karpenter node.