How to Differentiate ElastiCache Redis vs Valkey Costs Using CUR and Athena

Overview

Organizations running both ElastiCache for Redis and ElastiCache for Valkey often need to track costs per engine, for migration ROI, chargeback, or billing validation. The CUR product_cache_engine field provides exactly this visibility. This guide shows how to query it with Athena to get a per-engine cost breakdown across accounts.

Prerequisites

• AWS Cost and Usage Report enabled and configured
• CUR data integrated with Amazon Athena
• Appropriate IAM permissions for Athena queries

The Athena Query

Query to list all ElastiCache Redis and Valkey clusters from CUR

SELECT DISTINCT
  line_item_usage_account_id as account_id,
  SPLIT_PART(line_item_resource_id, ':', 7) as cluster_id,
  product_cache_engine as cache_engine,
  SPLIT_PART(line_item_usage_type, ':', 2) as instance_type,
  product_location as region
FROM "your_cur_table_name"  -- Replace with your actual CUR table name
WHERE line_item_product_code = 'AmazonElastiCache'
  AND product_cache_engine IN ('Redis', 'Valkey')
  AND line_item_line_item_type IN ('DiscountedUsage', 'Usage')
ORDER BY cache_engine, account_id, cluster_id;

Query Explanation

• line_item_usage_account_id: Identifies the AWS account running the cluster
• SPLIT_PART(line_item_resource_id, ':', 7): Extracts cluster ID from the resource ARN
• product_cache_engine IN ('Redis', 'Valkey'): Filters for specific cache engines

What the Results Include Account ID, Cluster ID, Cache engine (Redis or Valkey), Instance type/size, AWS Region

Alternative: Cost Explorer API Operation Filter

While Cost Explorer doesn't expose a dedicated "Database Engine" dimension, you can use the API Operation (Usage Type) filter/group-by to differentiate between Redis and Valkey usage:

• CreateCacheCluster:0002 → Redis usage
• CreateCacheCluster:Valkey → Valkey usage

This is available in the Cost Explorer console under Group by → Usage Type or via the Cost Explorer API using the USAGE_TYPE dimension. This approach doesn't require CUR access or Athena queries, making it accessible to FinOps stakeholders without SQL expertise.