ElastiCache Serverless — New feature
Amazon ElastiCache Serverless is a serverless option that helps you create a highly available cache in under a minute without infrastructure provisioning or configuration. ElastiCache Serverless 提供最高到 5TB 內存可用空間，讓客戶不需要預先去超額的資源，就能夠動態的提升資源，但使用上請先做足夠的壓測，來確保 “操作延遲(command latency)” 符合您的業務需求。
[+] AWS announces Amazon ElastiCache Serverless:
https://aws.amazon.com/tw/about-aws/whats-new/2023/11/amazon-elasticache-serverless/
[+] Amazon ElastiCache Serverless for Redis and Memcached is now available | AWS News Blog:
https://aws.amazon.com/tw/blogs/aws/amazon-elasticache-serverless-for-redis-and-memcached-now-generally-available/
Supprot Engine
- Redis 7.1+
- Memcached 1.6.20
Spec for Redis
- Cluster mode enable (CME only) by default ← No CMD mode.
- Encryption in transit: Always enabled ← Can’t disable, TLS/SSL by default.
- Encryption at reset: Always enabled ← Can’t disable.
- Automated backups : Disable by default (Modifiable)。
- Subnet group ← Multi-AZ by default (不能關) ← AZ 至少選要 2 個，沒有 single AZ。
- Redis Pub/Sub: Support.
- Single endpoint, and using 6379 for Write and 6380 for Read.
- primary: my-cluster.ec.com:6379
- replica: my-cluster.ec.com:6380
- Automated maintenance
- Maximum capacity limis
- CachedDataCapacity limit. Must be between 1 and 5000. ← Memory up to 5TB
- ECPUPerSecond limit. Must be between 1000 and 15000000.
No support for Redis now.
- Data Tiering。
- Global Data Store (Cross region replication)。
- Redis Client side caching ←- Redis 7 現有的功能，推測 pub/sub 應該也不支援。
- Redis functions ←- Redis 7 現有的功能。
Spec for Memcachd
- Single Endpoint : No need for memcached auto-discovery without cluster topology management
- Port: 11211 and 11212 for Read
- Auto-Scale by memory, CPU, Network IO.
- Support backup and restore (New feature)
- Encryption in transit: Always enabled ← Can’t disable, TLS/SSL by default.
- Encryption at reset: Always enabled ← Can’t disable.
- Engine version: 1.6.20
- maxmemory-policy: allkeys-lru
- maxmemory-policy-durability: noeviction
- Maximum usage limits
- Memory: 1~5000GB
- Compute: 1000~15,000,000 ECPUs
General ElastiCache Serverless FAQ
Q: How do I migrate an existing Amazon ElastiCache workload to ElastiCache Serverless?
You can move an existing Amazon ElastiCache workload by changing the Redis or Memcached endpoint to your new ElastiCache Serverless cache endpoint in your application. You can migrate existing ElastiCache data to ElastiCache Serverless by specifying the Amazon Simple Storage Service (Amazon S3) location of a backup file. Visit our ElastiCache Serverless documentation to learn more about migrating your workloads.
Q: Which versions of Redis and Memcached does Amazon ElastiCache Serverless support?
Amazon ElastiCache Serverless supports ElastiCache for Redis version 7.1 and ElastiCache for Memcached version 1.6.21 and above.
Q: How does Amazon ElastiCache Serverless scale?
Amazon ElastiCache Serverless continuously monitors your cache’s memory, compute, and network utilization to instantly scale. ElastiCache Serverless scales without downtime or performance degradation to the application by allowing the cache to scale up and initiating scale-out in parallel, to meet application requirements just in time. Visit our ElastiCache Serverless documentation to learn more about scaling.
Q: What is the Amazon ElastiCache Serverless availability Service Level Agreement (SLA)?
Amazon ElastiCache Serverless automatically stores data redundantly across multiple Availability Zones (AZs) and provides a 99.99% availability Service Level Agreement (SLA) for all workloads.
Q: What is Amazon ElastiCache Serverless pricing?
With Amazon ElastiCache Serverless, you only pay for the data you store and the compute your application uses.
Data stored: You pay for data stored in ElastiCache Serverless billed in gigabyte-hours (GB-hrs). ElastiCache Serverless continuously monitors the amount of data stored in your cache, sampling multiple times per minute, and calculates an hourly average to determine the cache’s data storage usage in GB-hrs. Each ElastiCache Serverless cache is metered for a minimum of 1 GB of data stored.
ElastiCache Processing Units (ECPUs): You pay for ElastiCache Serverless requests in ElastiCache Processing Units (ECPUs), a unit that includes both vCPU time and data transferred. Reads and writes require 1 ECPU for each kilobyte (KB) of data transferred. For example, a GET command that transfers 3.2 KB of data will consume 3.2 ECPUs. Commands that require additional vCPU time or transfer more than 1 KB of data will consume proportionally more ECPUs.
Minimum metered Data Storage: 1 GB per cache
