Features

A Key-Value store

• Uses memcached as the data store

Zone Based Replication

• Can create clusters based on availability zone for an EVCache app. This improves reliability and availability of the data.

Zone Affinity for Reads

• Eliminate cross zone traffic and improve the latency by reading the data from the local zone.

Dynamically re-sizable cluster

• The cluster size can be changed by adding or removing nodes. The EVCache client automatically configures (Eureka) to the new size.

Connection Pools and Management

• Create a Pool of connections to each EVCache App
• Separate pools for Read and Write Operations

Zone Fallback

• If a request to a zone fails (instance containing the data has crashed or the cluster size is increased causing a rehash of keys or a new ASG has been added) you can have clients fallback to other zones containing the data. This will incur an additional cost but typically is a lot smaller than going to the source of truth.

Set a zone to write only mode

• An availability zone can be set to "Write only Mode" until the cache is substantially full. In this mode all the reads from that zone will be sent to other zones.

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##Eureka Specific Features

Resilient to state in Eureka

• Be passive when disconnecting from EVCache server i.e. if eureka drops a server the client should not remove it until the connection is lost.