Cloud Infrastructure · Cluster
Cost Engineering
Unit economics and capacity planning.
- 01 Billing Units and Why a Cloud Bill Is an Estimate How usage records become invoice lines: instance-hours, the GB-month integral, minimum billing increments, and the order in which discounts are applied.
- 02 Allocating Shared Cost to a Unit of Work Why dividing a cluster bill by resource requests overcharges some tenants, how idle capacity hides in an allocation model, and where the normalization factor comes from.
- 03 Egress Boundaries and Which Bytes Are Billed Where traffic is metered in a cloud network, why the same byte can be free or charged twice depending on the path it takes, and how NAT and private endpoints move the boundary.
- 04 Storage Lifecycle Transitions and Minimum Durations How a lifecycle rule becomes a charge: the transition request, the per-object metadata charge in each class, minimum storage durations, and early-deletion fees.
- 05 Commitment Instruments and Break-Even Utilization What a reserved-capacity or savings-plan discount actually buys, how the hourly commitment becomes a sunk cost, and where the break-even utilization sits relative to list price.
- 06 Autoscaling Policies and the Cost of Headroom How a scaling policy converts a load signal into an instance count, why the control loop lags the load, and what each unit of headroom costs per month.
- 07 Instance Shape Selection and the vCPU-to-Memory Ratio Why a workload that fits one instance family strands half of another, how joint utilization percentiles differ from per-dimension ones, and what burstable credits hide.
- 08 Spot Capacity and the Price of Interruption How interruptible capacity is priced, why the discount is compensation for a termination notice, and how checkpoint interval trades against lost work.
- 09 Latency Targets and the Capacity Floor They Imply Why queueing delay grows without bound as utilization approaches one, how a p99 objective translates into a utilization ceiling, and what that ceiling costs per month.
- 10 Anomaly Detection on a Bill That Is Mostly Flat Why a fixed threshold catches nothing in a periodic cost series, how to model a baseline from history, and what a change in resource count does to a detector tuned for price.