Rightsize
Learn how Rightsize finds cost and performance improvements for your cloud resources.
Rightsize identifies cloud resources that cost more than they need to, or that do not have enough capacity for their workload. It recommends a better size for each one, based on how you actually use it.
How Rightsizing Works
Rightsize reads a resource's usage data over a lookback window. It calculates a high percentile of that usage, so one quiet week does not skew the recommendation. It adds a safety margin on top of that peak, then selects the smallest size that fits.
Rightsize re-analyzes every account every night. Saving a change in Rightsize settings also triggers an immediate recompute. Depending on the number of services and instances you have, the recompute can take up to 10 minutes.
The results on the page cover the last complete calendar month. For example, on October 15, the page shows results for September. A resource that you delete during the current month can still appear, because it existed during the month that the results cover. For an account without a complete month of data, the page shows results for the current month.
Each service has its own rules on top of this approach. The page for each service states what Rightsize recommends for it and how.
Services Rightsize Covers
Use the service selector at the top of the page to switch between services. Each service has its own cost chart, summary metrics, and table.
Lambda
AWS
A move to arm64, less provisioned concurrency, or a review of unused standing capacity
Monitoring Access
Rightsize needs to read utilization metrics before it can size anything.
AWS - grant access for your org, and separately for any linked account you want Rightsize to analyze. To grant access, update your North stack. See Update Your North Stack. Some region-specific restrictions cannot be resolved by granting access.
GCP - grant the Monitoring Viewer role, and add every project you want Rightsize to analyze to your billing project's metric scope. See Compute Engine.
If access is missing for an account or project, Rightsize cannot size its resources. They show as Insufficient data with the reason Monitoring access denied, and the default view hides them. A banner on each service tab shows how many resources are affected. Select Show affected resources to see them. When Rightsize cannot read metrics for any resource on the account, the page shows a request to grant access in place of the table.
Using the Rightsize Page
The page shows a cost chart, summary metrics for the selected service, and a table of individual resource recommendations.
Cost chart - shows the selected service's spend. Switch between Amortized and Unblended to change the chart's cost basis.
Summary metrics - Available Savings is the total monthly savings across the selected service's resources. The other tiles show counts of findings, plus the share of resources that are Tagged versus Untagged.
Filters - narrow the table by State, Type, Region, Reason, or Cohort.
Use the All accounts filter to narrow the table to one or more linked accounts or projects. It appears when there is more than one.
Non-Optimized is on by default. It hides Optimized, Insufficient data, and Not analyzed resources. Turn it off, or choose states in the State filter, to see them.
Tag filters - use the Filter button to filter by tag key and value.
Search - find a specific resource by name.
Share - if you have write permission on Rightsize, you can share Rightsize findings with others in your organization via email, Slack, or Jira. Select one or more rows with the checkboxes, then choose Share. Email and Slack shares are limited to 50 resources at a time.
Click a row's AI Suggestion button to open that resource's panel. The panel shows the resource's current state, the recommendation, the findings behind it, and its utilization history. Optimized rows have no button, except on the RDS tab. A row with no recommendation shows its reason in that column instead. Click the reason to open the panel.
Rightsize Settings
Click the gear icon (Account Preferences) to open Rightsize settings, where you control how Rightsize analyzes your account.
Reading utilization metrics has a small cost, billed by your cloud provider. The exact amount depends on the settings you choose below, and the Spend guardrail settings cap it.
Profile - choose Conservative, Balanced, or Aggressive. Balanced is the default. Conservative uses wide safety margins and only recommends clear wins. Aggressive uses the tightest margins and surfaces the most savings.
Never touch - exclude specific resources, or anything carrying a tag you choose. Excluding a member of a group excludes the whole group.
Spend guardrail - set two limits. Every service shares them.
Analysis cost floor - resources that cost less than this each month are not analyzed.
Monthly metrics budget - a monthly budget for the metric reads that Rightsize makes on your account. When the budget is used up, Rightsize defers further reads. Raise the budget to resume analysis.
Advanced - manually set any individual value behind your chosen profile, grouped as:
Coverage & cadence - Spend coverage, Cost change threshold, and Max result age. With Spend coverage, Rightsize analyzes the most expensive resources until they reach this share of total spend. The other two set when Rightsize analyzes a resource again: after a change in its monthly cost, or after a number of days.
Sizing - Metric lookback, CPU percentile, CPU headroom, and Memory headroom. Metric lookback is how many days of past utilization each recommendation uses.
Savings floors - Min savings and Min savings percent. Rightsize hides a recommendation that saves less than this amount each month, or less than this share of the resource's current cost.
Per-service overrides - set values for one service. Select the service, then fill the fields you want to override. An empty field uses the account default shown in that field. Reset to account default clears every override for that service.
You need write permission on Rightsize to open these settings. Without it, the gear icon is turned off. See IAM Permissions, or ask your org admin.
Understanding Each Finding
Every analyzed resource gets a finding: a state that summarizes the result, and one or more reasons behind it. Use these to see, at a glance, what Rightsize calculated for a resource and why, before you act on it.
Finding States
Each finding has one state:
Over provisioned
The resource is bigger than its usage needs. A smaller option is recommended.
Under provisioned
Usage is close to the limit of the current size. A bigger option is recommended.
Optimized
The current size is already the right one.
Not optimized
A cost improvement exists that is not a size change. For example, a volume with provisioned performance that it does not use, or a Lambda function that costs less on arm64.
Insufficient data
Rightsize did not have enough data to size the resource, so it made no recommendation.
Not analyzed
The resource is deliberately out of scope, for example Spot capacity.
Rightsize also flags a resource as Idle when it shows no meaningful activity. Idle is separate from the state. It has its own column in the table and its own tile in the summary metrics.
Finding Reasons
Each finding has one or more reasons: which metric it is based on, why a recommendation was capped, or why none could be made. Check these before you act on a recommendation, to understand what it is actually based on.
The table's Reasons column shows a count of how many reasons apply to a resource. Click a row's AI Suggestion button to see them as Findings chips on that resource's panel.
Most reasons are specific to the service. However, there are a few that apply across all services:
Monitoring access denied - Rightsize does not have the monitoring grant needed to read this resource's utilization metrics. See Monitoring Access, above.
Region restricted - the resource sits in an isolated AWS partition that North's commercial connection cannot reach, such as AWS GovCloud or a China region. Granting more access does not change this, because the partition is unreachable rather than unauthorized. Rightsize skips these resources before it reads any metrics, so they cost you nothing.
Linked account missing - Rightsize could not identify which linked account in your AWS Organization owns this resource.
Covered by a commitment - a Reserved Instance, Savings Plan, or Committed Use Discount covers at least half of the resource's usage. Rightsize still analyzes it. The saving is estimated at the resource's blended commitment rate, and the panel shows "Estimated at your commitment's blended rate." Resizing a resource does not cancel its commitment.
Deferred to a later run / Carried from the previous run - the resource is queued for a later analysis, or its last result was reused because nothing changed enough to re-check it.
Why a Resource May Have No Recommendation
A row with no recommendation shows a short reason in the AI Suggestion column, for example "Grant monitoring access to size this resource." Click the reason to open a panel with more detail and the reasons as chips. For a Google Cloud resource without monitoring access, the panel also has a Grant access button.
A resource marked Region restricted shows "North cannot reach this region from your account connection". No action on your side makes it analyzable. When no specific reason applies, the column shows "No recommendation for this resource." Each service page lists the cases that apply to it.
Why Some Recommendations Might Be Missing
Sometimes Rightsize cannot show some or all of your recommendations. A message on the page shows the reason. The list below includes a few examples of such messages.
Analyzing this account… - the first analysis of the account is running. The page refreshes automatically, so you can leave and come back.
Analysis is temporarily off. - analysis is paused. Recommendations refresh when analysis resumes. Your settings and history are unaffected.
Rightsize is not enabled for this account. - Rightsize is not turned on for the selected account.
Results don't currently include - a banner that shows how many accounts the results leave out, and which ones. The other results stay on the page.
Could not load recommendations. - the results failed to load. Try again in a few minutes.
You don't have access to this account's recommendations. - your North user cannot view this account. Switch to an account you manage, or ask an administrator for access.
When the table is empty, a line above it shows the reason. For example, it shows how many resources fell below the analysis cost floor, or that the monthly metrics budget is used up. Raise the budget in Rightsize settings to resume analysis.
Acting on a Recommendation
When you have acted on a recommendation, or when one does not fit your resource, record that from the resource's panel. Both actions need write permission on Rightsize.
Already resolved - confirms that you reviewed and resolved the recommendation. Rightsize removes it from your shortlist.
Not a good suggestion? - confirms that the recommendation is not relevant. North uses your feedback for future Rightsize recommendations.
Limitations
Rightsize only recommends. It never changes, resizes, or stops a resource on your behalf.
GPU-accelerated instances are not sized. Rightsize sizes on CPU, memory, and network metrics. A GPU-accelerated instance's size depends on its GPUs, which those metrics do not measure.
Spot instances are not sized. Spot capacity is reclaimed and priced on different terms, so Rightsize does not size it.
Rightsize is not available for Azure accounts.
Resources in isolated AWS partitions, such as AWS GovCloud and China regions, are not analyzed. North's commercial connection cannot reach those partitions.
Settings apply to your whole account today, not to individual member accounts within it.
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