# Caching strategy
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The ECS architecture implements a multi-layer caching strategy to optimize performance and reduce latency.

 **In-memory cache** 
+ Each ECS task maintains local caches for transformation policies and origin mappings
+ Cache is populated during task startup from DynamoDB
+ Fast lookup times for frequently accessed configurations

 **Cache initialization** 

1. New ECS tasks query DynamoDB during startup

1. All transformation policies are loaded into memory

1. Origin mappings are stored in optimized data structures

 **Cache invalidation** 
+ Rolling deployment strategy updates all ECS tasks with new configurations
+ Eventual consistency model balances performance with data freshness
+ Cache refresh typically takes up to 5 minutes

 **Cache consistency** 
+ New ECS tasks always load the latest configuration data
+ Existing tasks maintain cached data until manual refresh or natural replacement
+ Auto-scaling events automatically provision tasks with current data
+ Stale cache scenarios are resolved through the rolling update process