Create a Cloud Function that consumes the Monitoring API. Create a schedule to trigger the Cloud Function hourly and alert you if the average memory consumption is outside the defined range.

In Cloud Monitoring, create an alerting policy to notify you if the average memory consumption is outside the defined range.

Create a Cloud Function that runs on a schedule, executes kubectl top on all the workloads on the cluster, and sends an email alert if the average memory consumption is outside the defined range.

Write a script that pulls the memory consumption of the instance at the OS level and sends an email alert if the average memory consumption is outside the defined range.