Redis

DIAL Core keeps volatile data in Redis for fast access: cached resources, writes waiting to be synced to blob storage, per-request API keys, per-trace usage records, and coordination between Core instances. These static settings connect Core to a single Redis server, a Redis cluster, or a managed cache with IAM authentication. This page is for platform engineers who provision Redis for Core.

Connection

Set exactly one of the two connection settings.

Setting	Default	Description
redis.singleServerConfig.address	—	The address of a single Redis server, for example redis://redis:6379.
redis.clusterServersConfig.nodeAddresses	—	A JSON array of Redis cluster node addresses, for example ["redis://host1:6379","redis://host2:6379"].

Managed Redis with IAM authentication

redis.provider.* turns on provider-specific authentication.

Setting	Applies to	Description
redis.provider.name	All	The provider: aws-elasti-cache (IAM authentication), gcp-memory-store (access control), or azure-redis-cache (managed identity).
redis.provider.userId	aws-elasti-cache	The IAM-enabled user ID.
redis.provider.region	aws-elasti-cache	The region of the cache.
redis.provider.clusterName	aws-elasti-cache	The cluster name.
redis.provider.serverless	aws-elasti-cache	Whether the cache is serverless.
redis.provider.accountName	gcp-memory-store	The service account resource name, in the form projects/-/serviceAccounts/{ACCOUNT_EMAIL_OR_UNIQUEID}. The - wildcard is required; a project ID in its place is invalid.

{
  "redis": {
    "clusterServersConfig": {
      "nodeAddresses": ["rediss://dial-cache.example.cache.amazonaws.com:6379"]
    },
    "provider": {
      "name": "aws-elasti-cache",
      "userId": "dial-core",
      "region": "eu-west-1",
      "clusterName": "dial-cache",
      "serverless": false
    }
  }
}

Memory and eviction

Redis can run as a cache with a volatile-* eviction policy, for example:

maxmemory 4G
maxmemory-policy volatile-lfu

Some data lives only in Redis and has a TTL, so these policies can evict it under memory pressure:

• Per-request API keys (perRequestApiKey.ttl).
• Per-trace usage records (deploymentStats.ttlMs). An evicted record loses its trace's roll-up: aggCost in the analytics log, statistics.usage_per_model, and the aggregated costs the limits API reports. Limit enforcement is not affected.

Size maxmemory so that eviction stays rare. For the Redis server settings in Docker Compose, see Quick start and Advanced setup.

Further reading

• Resources — what Core caches in Redis and when it syncs to blob storage
• Storage — blob storage settings and provider requirements
• High availability — run Redis and Core for resilience
• Quick Start — the ready-made Compose setups and how to run them
• Core, Redis & Themes — the Core, Redis, and Themes service definitions