Opportunity Name:
Redshift Purchase Serverless Reservations
AWS Resource Type:
Amazon Redshift Serverless
Opportunity Description:
Amazon Redshift Serverless bills compute by RPU-hour at an on-demand rate unless you commit to a Reservation, which trades a term commitment for a discounted rate. This opportunity analyzes your payer account's actual Redshift Serverless usage pattern — not a generic estimate — and recommends a right-sized Reservation: how many RPUs to reserve, for what term, and under which payment option, based on whichever combination yields the greatest amortized saving.
This is a separate opportunity from CloudFix's existing Redshift Reserved Instances recommendation, which covers provisioned Redshift clusters. Serverless compute is billed and reserved in RPUs, not instance-hours, so it needs its own sizing logic — and it is not something AWS Cost Explorer can recommend, since Cost Explorer's reservation recommendations don't cover Redshift Serverless RPUs.
Criteria for identifying the opportunity:
- The payer account has at least the minimum hours of observed Redshift Serverless usage across linked accounts (default 336 hours — two weeks' worth) within the lookback window.
- CloudFix analyzes your last 30 or 60 days of usage (your choice; 30 is the default) to size the recommendation — a shorter window can't reliably distinguish a weekly usage cycle from a consistently high floor of usage.
- The recommendation nets out any Reservations you already hold, so you are only shown the additional commitment that would still save money, not a duplicate of what you've already purchased.
- The projected annual saving from the recommended term/payment option exceeds a minimum threshold (default $100).
Potential savings (range in % on annual basis):
- Varies by account and by the term/payment option chosen. CloudFix evaluates 1-year and 3-year terms, each with No Upfront or All Upfront payment (there is no Partial Upfront option for Serverless Reservations), and by default recommends whichever combination yields the greatest amortized saving for your usage.
Can CloudFix implement the fix automatically once I accept the recommendation?
No, and this one is by design rather than a limitation to be added later. A Redshift Serverless Reservation cannot be changed or canceled once purchased, and an All Upfront purchase is charged in full immediately — this is exactly the kind of binding financial commitment CloudFix does not make on your behalf. You purchase the Reservation yourself, at the payer account, from the Redshift console or API.
Other considerations:
- A Reservation is billed every hour of its term whether or not you actually consume the reserved RPUs — if your usage drops significantly after purchasing, you continue paying for the full commitment.
- Purchase happens at the payer account, and the discount then applies across all linked accounts' workgroups in that Region only — it does not carry over to other Regions.
- You can pin a specific term and payment option instead of accepting CloudFix's automatic best-savings pick, if your organization has a preference (for example, avoiding a large upfront payment even if it saves more over the term).
Bill Gleeson
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