ElastiCache vs Render Key Value: autoscaling or resize downtime

See how resize interruptions, connection limits, and replicated RAM pricing affect the choice between ElastiCache for Valkey and Render Key Value.

Amazon ElastiCache and Render Key Value icons with Momento branding

ElastiCache for Valkey gives AWS teams automatic scaling options. Render Key Value fits applications already on Render, with Valkey 8 for new instances, but capacity upgrades interrupt service for about 1–2 minutes. The deciding question is how your cache will grow. Render ties connection allowances to memory plans, while ElastiCache’s deployment choice shapes scaling and client integration.

At a glance

DimensionElastiCache for ValkeyRender Key Value
price (w/ 2 replicas)from $24.67/GB-monthfrom $27/GB-month
availabilityAWSRender cloud
engine + versionValkey 9Valkey 8 or Redis 6
uptime SLA99.99%unknown
support SLAfrom 5 minutesunknown
autoscalingvia Cloudwatch / Application Auto-Scalingnot supported
maximum size50 TB+40 GB

About Amazon ElastiCache

Amazon ElastiCache is an AWS-managed caching service with Serverless and node-based deployment options. ElastiCache for Valkey runs the Valkey engine, while Redis OSS is a related offering. AWS manages infrastructure maintenance. Customers choose the deployment model and, for node-based clusters, the capacity and topology.

About Render Key Value

Render Key Value is Render’s hosted key-value service. New instances run Valkey 8, while legacy instances run Redis 6. Customers select a provisioned instance size, which determines its memory and connection limits.

Recent updates

September 2, 2026 - Momento introduced Cluster and Flex capacity for Momento Cache. Both provide dedicated, managed Valkey resources. Cluster exposes topology choices, while Flex selects topology within capacity bounds, giving teams a choice in how they configure capacity while Momento operates the cluster.

June 11, 2026 - Render added configurable persistence for paid instances. Disposable caches can select Off, while other workloads can retain persistence. Mode changes restart the instance, and moving to or from Off loses all data.

Plan the upgrade before the cache fills

Render’s capacity upgrades restart the instance, causing about 1–2 minutes of unavailability. Existing instances cannot be downgraded in place. The selected persistence mode determines what data survives a restart, so growth can mean both a service interruption and cache warming.

ElastiCache Serverless scales automatically, and node-based deployments also offer autoscaling. For an anticipated spike that exceeds Serverless scaling pace, AWS recommends pre-scaling at least 60 minutes ahead.

Size for the application fleet, not just the dataset

Render’s published plans couple memory and connections. The 1 GB plan allows 1,000 connections, while the largest published 40 GB plan allows 40,000. A growing fleet can reach its connection allowance while its dataset still fits comfortably.

ElastiCache’s deployment model changes how clients connect. Serverless requires cluster-capable clients and TLS. Node-based deployments offer both cluster modes.

Render provides private access within the same workspace and region, making placement straightforward for applications already there. ElastiCache clusters have no public IP, but applications outside AWS can connect through supported networking arrangements.

Try Momento Cache

If your application fleet is growing faster than its dataset, Momento Cache offers a gateway designed for millions of clients.

Momento Cache puts dedicated, high-performance Valkey behind a managed gateway that keeps client integration stable as your application grows. Choose Cluster for direct control over instance types, shards, and replicas, or Flex to set capacity and replication bounds while Momento selects the topology. Both include built-in autoscaling and fully managed cluster operations.

Talk to a Momento solution engineer to evaluate the capacity model and configuration that fit your workload.

Frequently asked questions

Which uptime commitments apply?

ElastiCache offers a 99.99% uptime SLA. Render’s Key Value uptime percentage is unknown from its public pricing and service information.

How quickly can support respond?

AWS support offers initial response from 5 minutes. Render’s initial support response target is unknown from its public plans.

Are new and older Render instances running the same engine?

New Key Value instances use Valkey 8. Instances created before February 12, 2025 use Redis 6 and continue operating without feature-version upgrades. Render has also scheduled security patches for both Redis and Valkey, as documented on October 8, 2025.