# Scalability

Cube Cloud also allows adding additional infrastructure to your deployment to
increase scalability and performance beyond what is available with each
Production Deployment.

## Auto-scaling of API instances

With a Production Cluster, 2 Cube API Instances are included. That said, it
is very common to use more, and [additional API instances][ref-limits] can be
added to your deployment to increase the throughput of your queries. A rough
estimate is that 1 Cube API Instance is needed for every 5-10
requests-per-second served. Cube API Instances can also auto-scale as needed.

To change how many Cube API instances are available in the Production Cluster,
go to the deployment’s <Btn>Settings</Btn> screen, and open
the <Btn>Configuration</Btn> tab. From this screen, you can set the minimum and
maximum number of Cube API instances for a deployment:

<Screenshot
  alt="Cube Cloud Deployment Settings page showing auto-scaling configuration options"
  src="https://ucarecdn.com/3b39c56f-d553-4612-b4f0-07084cc4b742/"
/>

## Sizing Cube Store workers

Cube Store Workers are used to build and persist pre-aggregations. Each Worker
has a **maximum of 150GB** of storage; [additional Cube Store
workers][ref-limits] can be added to your deployment to both increase storage
space and improve pre-aggregation performance. A **minimum of 2** Cube Store
Workers is required for pre-aggregations; this can be adjusted. For a rough
estimate, it will take approximately 2 Cube Store Workers per 4 GB of
pre-aggregated data per day.

<InfoBox>

Idle workers will automatically hibernate after 10 minutes of inactivity, and
will not consume CCUs until they are resumed. Workers are resumed automatically
when Cube receives a query that should be accelerated by a pre-aggregation, or
when a scheduled refresh is triggered.

</InfoBox>

To change the number of Cube Store Workers in a deployment, go to the
deployment’s <Btn>Settings</Btn> screen, and open the <Btn>Configuration</Btn>
tab. From this screen, you can set the number of Cube Store Workers from the
dropdown:

<Screenshot
  alt="Cube Cloud Deployment Settings page showing auto-scaling configuration options"
  src="https://ucarecdn.com/3b39c56f-d553-4612-b4f0-07084cc4b742/"
/>


[ref-limits]: /product/deployment/cloud/limits#resources