# Overprovisioned Base Capacity in Redshift Serverless Workgroups Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/overprovisioned-base-capacity-in-redshift-serverless-workgroups Redshift Serverless bills compute in RPU-hours for the capacity in use while queries run, and the base capacity setting of a workgroup determines the... By: PointFive Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) The short version Redshift Serverless bills compute in RPU-hours for the capacity in use while queries run, and the base capacity setting of a workgroup determines the capacity Redshift uses to serve queries. PointFive Research Cloud cost research at PointFive AWS service [AWS Redshift](https://www.pointfive.co/efficiency-hub/cloud-services/aws-redshift) Category [Databases](https://www.pointfive.co/efficiency-hub/service-category/databases) Reference CER-0366 Type Overprovisioned Resource ## Explanation Why the waste happens and who it affects. The default base capacity is 128 RPUs, and many workgroups are created with that default or with a value copied from a sizing exercise and never adjusted. When the workload is made of light dashboard queries, small ETL steps, zero-ETL refreshes or connection health checks, each active period is billed at the full base capacity even though a much smaller base would complete the same work at acceptable speed. The effect is amplified by the billing rules: usage is metered per second with a 60-second minimum charge, and AWS notes that capacity can stay at a higher level for a period after load falls. The Redshift documentation states that a higher base capacity yields better performance but also incurs higher costs, and its zero-ETL cost guidance recommends the lower 8 RPU base capacity where available. ## Billing model The pricing dimensions that drive this cost. Redshift Serverless compute is billed only while queries run, at a rate driven by the capacity in use. RPU-hours Compute billed for the capacity used in a given duration, in RPU-hours on a per-second basis, and not billed when no queries are running Base capacity The RPU level Redshift uses to serve queries, 128 RPUs by default and adjustable from 4 RPUs up to 512 (1024 in some Regions) Minimum charge Each period of usage is charged for at least 60 seconds of resource usage Scaled capacity Capacity added above the base for higher load is billed at the same RPU rate as base compute ## How to detect 5 checks to find it in your estate. - List workgroups and their base capacity (get-workgroup or the Workgroup configuration Limits tab) and flag workgroups still at the 128 RPU default or at a high value with no documented reason - Query SYS\_SERVERLESS\_USAGE to see charged\_seconds and compute\_capacity per minute; workgroups whose usage consists of many short periods at full base capacity are paying the base rate for light work - Review ComputeCapacity and ComputeSeconds in CloudWatch (AWS/Redshift-Serverless) together with query runtimes in SYS\_QUERY\_HISTORY; consistently short queries on a large base suggest the base can be lowered - Check for connection pools or BI tools sending frequent health-check queries; Redshift Serverless treats them as billable user activity, so they trigger compute charges at the workgroup's capacity even when no real workload runs - Confirm managed storage size before planning a reduction, because it constrains the minimum base capacity ## How to fix 5 ways to remove the waste. - Lower the base capacity with update-workgroup or the console, testing representative queries at each step; values are 4 RPUs, or multiples of 8 from 8 to 512, and editing the base capacity might cancel some running queries - Respect the documented limits: 4 RPUs supports up to 32 TB of managed storage, 8 or 16 RPUs up to 128 TB, and above 128 TB the base cannot be set below 32 RPUs; AWS also recommends 32 or more RPUs for tables with many columns and higher concurrency - For zero-ETL target workgroups, use the lower 8 RPU base capacity where available and lengthen REFRESH\_INTERVAL where immediate freshness is not needed - Use the price-performance target (for example toward Optimizes for cost) for workloads in the 8 to 512 RPU range, and set Max capacity to cap scaling above the base - Set a Maximum RPU hours usage limit per day, week or month with a log, alert or turn-off-user-queries action, and reduce connection-pool health-check frequency to avoid paying for keep-alive queries ## Documentation Vendor references for pricing and configuration. - [Compute capacity for Amazon Redshift Serverless docs.aws.amazon.com](https://docs.aws.amazon.com/redshift/latest/mgmt/serverless-capacity.html) - [Billing for on-demand compute capacity docs.aws.amazon.com](https://docs.aws.amazon.com/redshift/latest/mgmt/serverless-billing-on-demand.html) - [Billing for Amazon Redshift Serverless docs.aws.amazon.com](https://docs.aws.amazon.com/redshift/latest/mgmt/serverless-billing.html) - [Amazon Redshift Pricing aws.amazon.com](https://aws.amazon.com/redshift/pricing/) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - AWS Redshift CER-0363 ### [Inactive Redshift Provisioned Cluster](https://www.pointfive.co/efficiency-hub/inefficiencies/inactive-redshift-provisioned-cluster) A provisioned Amazon Redshift cluster bills every compute node for every hour it is available, whether or not any query runs. Clusters created for a proof of concept, a migration, a one-off analysis or a reporting workload that has since... Databases - AWS Redshift CER-0364 ### [Missing Pause Schedule for Non-Production Redshift Provisioned Clusters](https://www.pointfive.co/efficiency-hub/inefficiencies/missing-pause-schedule-for-non-production-redshift-provisioned-clusters) Development, test and staging Redshift provisioned clusters are typically used during working hours and by scheduled test runs, but they stay available around the clock because nobody set up a pause and resume schedule. Every night and... Databases - AWS Redshift CER-0365 ### [Low Reserved Node Coverage for Steady-State Redshift Provisioned Clusters](https://www.pointfive.co/efficiency-hub/inefficiencies/low-reserved-node-coverage-for-steady-state-redshift-provisioned-clusters) Production Redshift provisioned clusters usually run continuously with a fixed node type and node count for long periods, which is exactly the usage pattern reserved nodes are designed for. When those nodes are billed at on-demand rates,... Databases --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.