Unit
- Compute costs: Charges for virtual machines, containers, and serverless functions are based on instance type, vCPU count, memory, and runtime hours. Over-provisioning and idle resources are common waste sources.
- Storage costs: Fees accrue for data volume, access frequency, and retrieval operations. Block, object, and file storage each have distinct pricing models that influence total spend.
- Data transfer costs: Egress traffic between regions, availability zones, or to the internet incurs charges. Ingress is often free, but outbound rates can dominate unexpected bills.
- Network costs: Load balancers, NAT gateways, and VPN connections add fixed hourly costs plus data processing fees. Complex network topologies amplify expenses.
- Managed service costs: Database instances, message queues, and caching services incur per-resource fees. Choosing fully managed versus self-managed affects the cost-performance trade-off.
- License costs: Some cloud services include third-party licensing (e.g., Windows, SQL Server). Bring-your-own-license options can reduce costs if available.
- Reserved vs. on-demand pricing: Reserved instances offer discounts for upfront commitment, while on-demand provides flexibility at premium rates. The purchasing strategy directly impacts monthly bills.
- Hidden costs: Snapshot storage, unused IP addresses, and monitoring logs generate small charges that accumulate. Regular auditing uncovers these often-overlooked expenses.
Quick Revision
- Cloud costs stem from compute, storage, network, managed services, licenses, and hidden items.
- Over-provisioning and idle resources are primary waste sources.
- Data egress and complex networking significantly raise bills.
- Understanding each driver is the first step toward targeted optimization.