4.4 Cost Optimisation
Recommended
AWS Cost
Azure Cost
GCP Cost
Recommended
Recommended
Comprehensive
Purpose
Section titled “Purpose”Cost Optimisation focuses on delivering the solution at the lowest reasonable cost while meeting all other quality requirements. It covers cost-aware design decisions, cost analysis, and ongoing cost management practices. Evaluate this quality attribute across all architectural views documented in Section 3.
4.4.1 Cost Influence & Analysis
Section titled “4.4.1 Cost Influence & Analysis”Design Cost Decisions
Section titled “Design Cost Decisions”How do the design decisions in hosting, compute, networking, data storage, and resiliency demonstrate cost-effectiveness?
| Posture | Selected | Detail |
|---|---|---|
| Design decisions chosen for specific reasons other than cost | [ ] | [describe why] |
| Most cost-effective options intentionally not selected | [ ] | [describe why and the tradeoffs] |
| Most cost-effective options selected | [ ] | [describe the analysis] |
Cost Analysis
Section titled “Cost Analysis”Has cost analysis or modelling been performed to inform design decisions?
- No - A cost analysis has not been performed
- Yes - [describe the analysis approach, tools used (e.g., cloud pricing calculators, TCO models), and key findings]
4.4.2 Cost Implications
Section titled “4.4.2 Cost Implications”Has the design been constrained in ways that do not fully meet requirements because of cost?
- No - The design fully meets requirements; cost has not impacted the design
- Yes - [describe how and why cost constrained the design, and the impact]
4.4.3 FinOps Practices
Section titled “4.4.3 FinOps Practices”Document ongoing cost management practices:
| Practice | Implementation |
|---|---|
| Cost monitoring | [dashboards, alerts, tools] |
| Cost allocation | [tagging strategy, cost centres] |
| Reserved capacity | [reserved instances, savings plans, committed use] |
| Rightsizing reviews | [process and frequency for reviewing resource utilisation] |
| Waste elimination | [process for identifying and removing unused resources] |
| Budget governance | [budget alerts, approval thresholds] |
Guidance
Consider documenting:
- Expected monthly/annual run cost breakdown by component
- Cost comparison of alternatives considered
- Cost optimisation opportunities identified but deferred
- Triggers that would necessitate cost re-evaluation (e.g., scale events, contract renewals)
Scoring Guidance
| Score | What This Looks Like |
|---|---|
| 1 | Cost acknowledged as a concern but no analysis performed |
| 3 | Cost analysis completed, monitoring enabled, tagging strategy in place |
| 5 | All of the above plus reserved capacity assessed, right-sizing evidenced, cost model linked to cloud calculator, FinOps practices documented |