# Underutilized VM commitments due to architectural drift Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/underutilized-vm-commitments-due-to-architectural-drift VM-based Committed Use Discounts in GCP offer cost savings for predictable workloads, but they are rigid: they apply only to specified VM types,... By: Diana Lezcano Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) # Underutilized VM Commitments Due to Architectural Drift The short version VM-based Committed Use Discounts in GCP offer cost savings for predictable workloads, but they are rigid: they apply only to specified VM types, quantities, and regions. [Diana Lezcano](https://www.linkedin.com/in/diana-lezcano/) Strategic Advisor @ Ardent Cloud Strategy GCP service [GCP Compute Engine](https://www.pointfive.co/efficiency-hub/cloud-services/gcp-compute-engine) Category [Compute](https://www.pointfive.co/efficiency-hub/service-category/compute) Reference CER-0089 Type Underutilized Commitment ## Explanation Why the waste happens and who it affects. When organizations evolve their architecture - such as moving to GKE (Kubernetes), Cloud Run, or autoscaling - usage patterns often shift away from the original commitments. Resource-based CUDs cannot be cancelled, so when architectural shifts strand them, underutilized commitments lead to sustained, silent waste; Compute flexible (spend-based) CUDs offer more flexibility across regions, machine series, GKE, and Cloud Run, but only for eligible spend. This is especially common when workload changes go uncoordinated with finance or centralized planning. ## Billing model The pricing dimensions that drive this cost. CUDs are billed based on committed resource quantities (e.g., vCPUs, memory) for specific VM families and regions, regardless of actual usage. If consumption falls below the commitment level, the unused portion is still billed, generating cost with no value returned. ## How to detect 5 checks to find it in your estate. - Review actual usage against committed VM types and regions across a representative time period - Identify consistent underutilization of CUDs based on usage-to-commit ratio - Confirm whether architectural shifts (e.g., to GKE, Cloud Run, or autoscaling groups) have occurred - Check for commitments applied to workloads that have been decommissioned or scaled down - Evaluate whether commitments are isolated to specific projects, regions, or teams without visibility across the org ## How to fix 5 ways to remove the waste. - Consolidate workloads onto committed VM types where feasible - Avoid renewing commitments for workloads that are scaling down or migrating - Use Compute flexible (spend-based) CUDs when architectural flexibility is needed, and confirm resource-based CUD sharing across projects in the billing account is enabled - Implement cross-functional governance for forecasting and commitment approvals - Align future commitments with current and expected usage patterns, not historical ones ## Documentation Vendor references for pricing and configuration. - [Committed use discounts (CUDs) for Compute Engine docs.cloud.google.com](https://docs.cloud.google.com/compute/docs/instances/committed-use-discounts-overview) - [Resource-based committed use discounts docs.cloud.google.com](https://docs.cloud.google.com/compute/docs/instances/signing-up-committed-use-discounts) - [Spend-based committed use discounts docs.cloud.google.com](https://docs.cloud.google.com/docs/cuds-spend-based) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - GCP Compute Engine CER-0282 ### [Missed Use of Committed Use Discounts for Compute Engine](https://www.pointfive.co/efficiency-hub/inefficiencies/missed-use-of-committed-use-discounts-for-compute-engine) Workloads with predictable, long-running compute usage continue to run entirely on on-demand pricing instead of leveraging Committed Use Discounts. For stable environments, such as production services or continuously running batch... Compute - GCP Compute Engine CER-0095 ### [Missing Scheduled Shutdown for Non-Production Compute Engine Instances](https://www.pointfive.co/efficiency-hub/inefficiencies/missing-scheduled-shutdown-for-non-production-compute-engine-instances) Development and test environments on Compute Engine are commonly provisioned and left running around the clock, even if only used during business hours. This results in wasteful spend on compute time that could be eliminated by scheduling... Compute - GCP Compute Engine CER-0048 ### [Underutilized GCP VM Instance](https://www.pointfive.co/efficiency-hub/inefficiencies/underutilized-gcp-vm-instance) GCP VM instances are often provisioned with more CPU or memory than needed, especially when using custom machine types or legacy templates. If an instance consistently consumes only a small portion of its allocated resources, it likely... Compute --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.