Use the Vertical Pod Autoscaler (VPA) as the first choice to automatically adjust pod CPU/memory requests and avoid OOMKills. If you need scheduled jobs, multi-cloud prediction, framework-specific tuning, or a VPA dashboard, consider Kubecost, Densify, Kruize Autotune, Goldilocks, or Robusta KRR respectively.
3KubecostBest when you want scheduled, automated resizing jobs on EKS that adjust requests based on recent usage; caveat: primarily cost/visibility focused, so automation is tied to its EKS add-on features.51%
Kubernetes Vertical Pod Autoscaler (VPA) : An official Kubernetes sub-project that monitors container memory and CPU usage over time. It can operate in "Off" mode (providing recommendation reports) or "Auto" mode (which automatically restarts pods to apply updated resource values). Note: Automatic application restarts workloads, which can cause brief disruptions if not configured with a PodDisruptionBudget.
Cast AI : An all-in-one Kubernetes automation platform that includes automated right-sizing engines to continuously adjust CPU and memory requests based on real-time application profiles.
Tools that can automatically right-size Kubernetes resource requests include:
Cast AI — provides continuous workload rightsizing that adjusts CPU and memory requests based on usage patterns, with automated optimization features.
StormForge — uses machine learning to generate CPU/memory recommendations and can optionally apply them automatically through its tooling.
Kubernetes Vertical Pod Autoscaler (VPA) — built-in Kubernetes project component that can update workload resource requests based on observed usage; Auto mode can apply changes by recreating pods.
Fairwinds Goldilocks — uses VPA recommendations to show right-sized CPU/memory settings, but is primarily recommendation-based rather than a fully autonomous updater.
For pods being killed by memory limits (OOMKilled), prioritize tools that:
analyze memory peaks, not just averages;
account for startup spikes and traffic bursts;
can increase limits/requests safely;
understand interactions with HPA and stateful workloads.
A common progression is:
Start with VPA/Goldilocks to identify bad settings.
Use StormForge or Cast AI if you want continuous automated remediation.
Yes. There are several options, ranging from built-in Kubernetes automation to commercial ML-based tools:
Tool
Automatically changes requests?
Memory/OOM focus
Notes
Kubernetes VPA
Yes
Yes
Native Kubernetes approach. Recommends CPU/memory and can automatically apply changes; depending on mode, this may evict/recreate Pods.
StormForge
Yes
Yes
ML-based continuous rightsizing; can automatically deploy recommendations and lets you constrain min/max values and optimization goals.
CAST AI Workload Autoscaler
Yes
Yes
Commercial continuous rightsizing, including automated workload resource adjustments.
Goldilocks / Fairwinds
No
Yes
Open-source recommendation UI built around VPA. Good if you want humans/GitOps to approve changes.
KRR / Robusta
No
Yes
Open-source CLI that calculates recommendations from Prometheus-compatible metrics; useful for generating PRs rather than directly modifying workloads.
Kubecost
Primarily recommendations
Yes
Provides container request-rightsizing recommendations and estimated savings; useful if you're already using Kubecost for cost visibility.
For your specific problem
If Pods are actually getting OOMKilled, I'd distinguish two problems:
Requests are too high → you're wasting cluster capacity.
Memory limits are too low → the container gets killed when it exceeds the limit.
Rightsizing tools can address both, but simply lowering requests won't fix OOMKills. Kubernetes VPA, for example, explicitly incorporates historical usage, peaks, variance, and OOM events into its recommendations.
If you want open source + conservative rollout, I'd start with VPA in recommendation mode or Goldilocks, inspect the recommendations, and then automate application once you're comfortable.
If you want continuous automatic remediation with minimal human intervention, I'd investigate StormForge or CAST AI. StormForge specifically advertises automated CPU/memory rightsizing and controls for how aggressively recommendations are applied.
One important caveat: VPA's traditional automatic mode can evict Pods to apply new resources. Newer Kubernetes/VPA combinations have in-place resizing options, but their availability depends on your Kubernetes version and configuration.
If you tell me whether you're on EKS, GKE, AKS, or self-managed Kubernetes, and roughly how many workloads you have, I can narrow this down to the most appropriate 2–3 options.
Robusta KRR (Kubernetes Resource Recommender) : An open-source CLI tool that analyzes Prometheus metrics and outputs optimal CPU and memory request recommendations for manual or CI/CD application.[](https://cast.ai/blog/best-pod-rightsizing-tools/)
Fairwinds Goldilocks : An open-source controller that runs in your cluster, uses a VPA client to catch vertical sizing metrics, and displays a dashboard with memory and CPU recommendations.[](https://cast.ai/blog/best-pod-rightsizing-tools/)
Would you prefer an open-source recommendation tool (like Goldilocks or KRR) that keeps you in manual control, or an fully automated runtime platform (like ScaleOps or Cast AI) that adjusts requests on the fly?
Automated workload and cluster optimization, including pod rightsizing; particularly useful if you also want node provisioning/bin-packing optimization.
Kubernetes VPA
Medium–High
Native Vertical Pod Autoscaler can recommend or automatically change CPU/memory requests. Auto mode can evict/recreate pods, so disruption needs consideration.
Open-source VPA-based recommendations and dashboard. Excellent for determining sensible starting requests, but recommendations are normally applied manually.
Kubecost
Low–Medium
Primarily cost/visibility, but provides resource-rightsizing recommendations and can fit well if cost allocation is already a requirement.
For your specific problem
Since you're seeing OOMKilled pods, I'd distinguish two problems:
Requests too high → you're wasting cluster capacity.
Memory limits too low → the container actually gets killed when it exceeds its limit.
Rightsizing requests alone won't necessarily solve #2. You want a system that looks at memory peaks and historical behavior, not merely average utilization, and sets appropriate memory limits/requests with safety margins.
A practical progression would be:
Want open source / minimal cost: VPA + Goldilocks. Start in recommendation mode and inspect the memory recommendations. Goldilocks explicitly uses VPA's historical usage model.
Want automated remediation: StormForge, ScaleOps, or Cast AI.
Want broader cluster optimization too: Cast AI is worth evaluating because it combines workload rightsizing with node-level optimization.
Already have Prometheus and want an ML-based approach: StormForge integrates with Prometheus-compatible observability and can automatically apply recommendations through its Applier.
One important operational point: don't simply set memory limits equal to the VPA target for workloads with bursty memory consumption. Keep appropriate headroom and impose min/max guardrails; otherwise an automated optimizer can trade cost savings for more OOM kills.
If you tell me whether you're on EKS, GKE, AKS, or on-prem Kubernetes, and roughly how many workloads/pods you have, I can narrow this to the most relevant 2–3 architectures and show how they'd handle your OOMKilled problem.
Several platforms and native Kubernetes projects offer tools to handle resource right-sizing . They generally fall into two categories: fully automated (which apply changes or scale dynamically) and recommendation-based (which analyze usage and give you suggestions).[](https://cast.ai/blog/best-pod-rightsizing-tools/)
Here are the primary options available:
Fully Automated Right-Sizing Platforms
ScaleOps : Provides autonomous, real-time pod resource rightsizing that continuously monitors live workload behavior and adjusts CPU/memory requests automatically without requiring manual YAML updates.[](https://scaleops.com/product/automated-pod-rightsizing/)
Datadog : Features a DatadogPodAutoscaler utilizing in-place vertical scaling (on supported Kubernetes versions) to adjust resources on running containers dynamically or via safe rollouts.[](https://docs.datadoghq.com/containers/autoscaling/)
Native & Open-Source Tools (Recommendations or Auto-Mode)
Goldilocks (Fairwinds) : An open-source controller that works with the VPA to create a dashboard in your cluster, showing clear memory and CPU recommendations per deployment without altering your workloads.[](https://cast.ai/blog/best-pod-rightsizing-tools/)
To help narrow down the best fit, tell me:
Are you looking for a fully automated commercial platform or an open-source/native recommendation tool?
Are you already using a monitoring stack like Prometheus or Datadog in this cluster?
Kubernetes VPA — built-in ecosystem solution that can automatically adjust CPU/memory requests; Auto mode can evict pods.
Goldilocks (Fairwinds) — open-source VPA-based recommendations; safer, but generally requires you to apply changes.
KRR (Robusta) — Prometheus-based recommendations, useful for GitOps workflows.
Cast AI — commercial, continuous automated rightsizing, including OOM-aware workload optimization.
Kubecost — provides request-rightsizing recommendations and estimated savings, primarily as a cost-visibility/optimization platform.
For pods actually getting OOM-killed, I'd look first at VPA or an automated platform like Cast AI, rather than recommendation-only tools. Note that increasing a request alone doesn't prevent OOM kills caused by a too-low memory limit.
Several open-source projects, cloud-native vendors, and enterprise platforms offer tools to automatically right-size Kubernetes CPU and memory requests. They generally fall into native controllers, automated optimization platforms, and cost-monitoring tools with recommendations.
Kubecost : Primarily a cost-monitoring tool, Kubecost analyzes historical resource usage and provides specific, actionable container-level sizing recommendations for memory and CPU requests, which can also be integrated into automation pipelines.
Datadog Kubernetes Monitoring : Datadog tracks resource utilization metrics and surfaces rightsizing recommendations to help prevent Out-Of-Memory (OOM) kills or reclaim wasted cluster capacity. [](https://www.datadoghq.com/blog/kubernetes-autoscaling-datadog/)
Cast AI : An automated Kubernetes cost-optimization platform that includes autonomous sizing engines to dynamically adjust CPU and memory requests based on actual workload patterns.
To help narrow down the best fit, could you share:
Are you looking for an open-source project or an enterprise commercial tool?
Do you want something that automatically applies changes live, or a tool that generates pull requests/recommendations for review first?
ScaleOps offers an autonomous, fully automated pod rightsizing platform that continuously observes real production behavior and updates allocations live to prevent OOM kills and waste without human intervention. [](https://scaleops.com/product/automated-pod-rightsizing/)
Cast AI provides an automated workload autoscaler that optimizes and adjusts resource requests dynamically, minimizing pod disruptions while aligning allocations with actual workload demands. [](https://cast.ai/blog/best-pod-rightsizing-tools/)
Robusta KRR (Kubernetes Resource Recommender) is another prominent open-source CLI/recommendation tool that analyzes Prometheus metrics and outputs optimal resource requests for your deployments. [](https://cast.ai/blog/best-pod-rightsizing-tools/)
Kubecost focuses heavily on cost visibility, but it also includes built-in container-level right-sizing recommendations to help teams manually or programmatically adjust over- or under-provisioned memory limits.
To help narrow down the best fit, tell me:
Are you looking for a fully automated solution or an open-source recommendation tool you can review first?
Do you already run Prometheus or another metrics stack in your clusters?
Yes. There are several good options, ranging from Kubernetes-native recommendations to fully autonomous commercial tools:
StormForge — Probably the closest match to your problem. Its Optimize Live product continuously analyzes CPU/memory usage and automatically adjusts requests and limits, with controls for reliability vs. savings and HPA-aware behavior. It specifically targets under-provisioning and OOM errors.
CAST AI — Offers an autonomous workload autoscaler that continuously adjusts CPU and memory requests. It also supports automatic in-place resizing, so resource changes can be made without the traditional pod restart in supported Kubernetes configurations.
Fairwinds Goldilocks — Open source and excellent if you want recommendations rather than automatic changes. It uses Kubernetes VPA recommendations to show appropriate requests/limits for workloads.
Kubernetes VPA (Vertical Pod Autoscaler) — The native option. VPA can recommend or automatically adjust CPU/memory resources, though its automatic mode traditionally involves evicting/restarting pods.
KRR (Kubernetes Resource Recommendations) — An open-source CLI that analyzes Prometheus metrics and generates resource recommendations without requiring VPA. It's useful if you want something lightweight and GitOps-friendly.
ScaleOps — Another commercial option focused on continuous workload rightsizing and autoscaling. Current industry comparisons put it alongside StormForge and CAST AI for automated workload-level optimization.
What I'd choose for OOMKilled pods
If your primary problem is pods getting killed because memory requests/limits are too low, I'd evaluate them in this order:
StormForge — strongest direct fit for automated memory right-sizing with reliability guardrails.
CAST AI — particularly attractive if you also want node provisioning/bin-packing and broader cluster cost optimization.
VPA + Goldilocks — best low-cost/open-source starting point if you're comfortable reviewing and applying recommendations yourself.
One important distinction: requests don't directly cause an OOMKill. A container exceeding its memory limit is what normally triggers the OOM kill. So if you're seeing OOMKilled, you want tooling that can address both requests and limits, not merely reduce oversized requests. StormForge explicitly supports recommendations for both.
If you tell me whether you're on EKS, GKE, AKS, or self-managed Kubernetes, I can narrow this to the best 2–3 options and compare their automation, restart behavior, HPA compatibility, and pricing.
KRR (Kubernetes Resource Recommender by Robusta) : A CLI tool that scans your cluster and outputs CLI-friendly recommendations to CLI or Prometheus metrics on how to adjust requests.[](https://cast.ai/blog/best-pod-rightsizing-tools/)