> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cognite.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Limits and restrictions

> Learn about the limits and restrictions for data modeling resources in your CDF project.

Understanding these limits helps you plan your data modeling resource usage.

## Resource limits

The table lists the **default** limits for data modeling resources. The limits can be different for your CDF project depending on your specific configuration.

| Name                                                 | Default limit |
| ---------------------------------------------------- | ------------- |
| **Spaces**                                           | 100           |
| **Containers**                                       | 1,000         |
| - Container properties (total)                       | 25,000        |
| - Container properties (per container)               | 100           |
| - Container properties (per container, records only) | 1,000         |
| - Values in an enum container property               | 32            |
| **Views**                                            |               |
| - View versions (total)                              | 2,000         |
| - View versions (per view)                           | 100           |
| - View properties (per view)                         | 300           |
| - Implemented views (per view)                       | 10            |
| **Data models**                                      |               |
| - Data model versions (total)                        | 500           |
| - Data model versions (per data model)               | 100           |
| - Views (per data model)                             | 100           |
| **Instances**                                        |               |
| Live instances                                       | 5,000,000     |
| Soft deleted instances                               | 10,000,000    |
| **Streams**                                          |               |
| Active streams                                       | 3             |
| Soft-deleted streams                                 | 30            |

For stream template specifications, including maximum record counts, data volumes, throughput limits, and retention periods, see [Records and streams](/cdf/dm/records/concepts/records_and_streams).

## Property value limits

These limits apply to the values of container properties:

| Data type         | Maximum size          |
| ----------------- | --------------------- |
| `text` properties | 128,000 bytes (UTF-8) |
| `json` properties | 40,960 bytes (UTF-8)  |
| List properties   | See below.            |

### List size limits

By default, list properties have these size constraints:

* **Direct relations**: maximum 100 items
* **Other types**: maximum 1,000 items

You can customize the limits by setting the `maxListSize` parameter on container properties.

You can only increase (not decrease) the `maxListSize` parameter after creating a container property. The maximum values for `maxListSize` are:

* 600 for `int32` properties with a b-tree index.
* 300 for `int64` properties with a b-tree index.
* 2,000 for all other property types.

## Concurrency limits

Concurrency limits control how many API operations can run simultaneously on your CDF project.

The table lists the **default** concurrency limits for a CDF project. The limits can be different for your CDF project depending on your specific configuration.

| Operation type             | Default concurrency limit |
| -------------------------- | ------------------------- |
| Instance apply operations  | 4                         |
| Instance delete operations | 2                         |
| Instance query operations  | 8                         |

Transformations can use a maximum of 75% of the budget while the remaining 25% is reserved for other clients.

Concurrency limits are applied project-wide, not per client. If a request exceeds any of the concurrency limits, it will be throttled with a `429 Too Many Requests` response. Learn more about [API rate limits](/api-reference/concepts/20230101/rate-limits).

<Note>
  If you are using official Cognite SDKs, throttled requests are automatically retried with exponential backoff. If you are making request without using an official SDK, make sure that you are using an appropriate retry strategy to handle 429 responses.
</Note>

## Need higher limits?

If you need increased limits for your CDF project, contact [Cognite Support](https://cognite.zendesk.com/hc/en-us/requests/new).

## Monitoring resource usage

To view the current limits and usage statistics for your CDF project:

<Steps>
  <Step title="Navigate to the Data models page">
    In the <span class="ui-element">Data fusion</span> workspace, select <span class="ui-element">Data models</span>.
  </Step>

  <Step title="View the limits and usage statistics">
    On the <span class="ui-element">Data models</span> page, under <span class="ui-element">Storage</span>, select <span class="ui-element">See all</span> to view your project-specific limits and current usage statistics.
  </Step>
</Steps>

### Monitoring resource usage programmatically

To retrieve limits and usage statistics programmatically:

* Use the [/statistics](/api-reference/concepts/20230101/dm-statistics) endpoint for project-wide statistics.
* Use the [/statistics/space](/api-reference/concepts/20230101/dm-statistics) endpoint for space-specific statistics.

## Reserved values

The following values are reserved for Cognite internal use and cannot be used in your data models.

### Views and containers

**Reserved `externalId` values**:

* `Boolean`, `Date`, `Float32`, `Float64`, `Float`, `Int32`, `Int64`, `Int`
* `JSONObject`, `Mutation`, `Numeric`, `PageInfo`, `Query`, `String`
* `Subscription`, `TimeSeries`, `File`, `Sequence`, `Timestamp`

**Reserved `properties` values**:

* `createdTime`, `deletedTime`, `edge_id`, `extensions`, `externalId`
* `lastUpdatedTime`, `node_id`, `project_id`, `property_group`
* `seq`, `space`, `version`, `tg_table_name`, `startNode`, `endNode`

**Reserved enum value names**:

* `"true"`, `"false"`, `"null"`

### Spaces

**Reserved `space` values**:

* `cdf`, `dms`, `edge`, `node`, `pg3`, `shared`, `space`, `mapping`, `system`
* `constraint`, `edge_source`, `history`, `identifier_by_space`, `index`
* `node_source`, `project`, `property_group_constraint`, `property_group_index`
* `property_group`, `property`, `version_info`