# Cache

## Memorystore

Memory Store is a fully managed in-memory cache service having protocol compatibility with Redis and Memcached. See documentations for [Memorystore Redis](https://cloud.google.com/memorystore/docs/redis/) and [Memorystore Memcached](https://cloud.google.com/memorystore/docs/memcached) (beta) for more information.

#### Zonal Resource

Memorystore is zonal, meaning each Memorystore instance is only available within a zone, or accessible from other zones within the same region. For high-availability, create a **Standard** tier instance, which includes a failover replica in a separate zone.

#### Connectivity

All Memorystore instances can only be accessed by a private IP on a VPC network. You can connect to a Memorystore instance from different Google Cloud Platform computing resources differently. In general, VM-based products (Compute Engine, Kubernetes Engine, and App Engine Flexible) requires the VM to be on the same VPC, and Serverless products requires [VPC Service Connector](https://cloud.google.com/vpc/docs/configure-serverless-vpc-access).

| Resource            | Method                                                                                             |
| ------------------- | -------------------------------------------------------------------------------------------------- |
| Compute Engine      | Out-of-the-box                                                                                     |
| Kubernetes Engine   | [VPC-Native cluster](https://cloud.google.com/kubernetes-engine/docs/how-to/alias-ips)             |
| App Engine Flexible | [Additional Configuration](https://cloud.google.com/appengine/docs/flexible/java/using-shared-vpc) |
| App Engine Standard | [VPC Service Connector](https://cloud.google.com/appengine/docs/standard/java11/connecting-vpc)    |
| Cloud Run           | [VPC Service Connector](https://cloud.google.com/run/docs/configuring/connecting-vpc)              |
| Cloud Function      | [VPC Service Connector](https://cloud.google.com/functions/docs/networking/connecting-vpc)         |

#### Protocol Compatibility

Because Memorystore is protocol compatible. You can use existing Spring Boot integration with Redis and Memcached as-is.

{% content-ref url="cache/memorystore-redis" %}
[memorystore-redis](https://spring-gcp.saturnism.me/app-dev/cloud-services/cache/memorystore-redis)
{% endcontent-ref %}

{% content-ref url="cache/memorystore-memcached" %}
[memorystore-memcached](https://spring-gcp.saturnism.me/app-dev/cloud-services/cache/memorystore-memcached)
{% endcontent-ref %}