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

# History time to live

Each execution of a model resource (BPMN, DMN, and CMMN) generates historic data during execution that is stored in the database. In ASEE Flow, [history cleanup](/user-guide/process-engine/history) removes this historic data from the database based on a defined **history time to live (HTTL)**.

You must configure HTTL in one of the following ways:

* Define HTTL per model directly in Desktop Modeler.
* Set a default HTTL via an engine configuration.
* Switch off the HTTL check via an engine configuration if history cleanup is not used.

### Values

Process instances are only cleaned up if their corresponding definition has a valid time to live (TTL). Use the `historyTimeToLive` extension attribute of the process definition to define the TTL for all its instances:

`<process id="oneTaskProcess" name="The One Task Process" isExecutable="true" camunda:historyTimeToLive="5"></process>`

TTL can also be defined in ISO-8601 date format. The function only accepts the notation to define the number of days.

`<process id="oneTaskProcess" name="The One Task Process" isExecutable="true" camunda:historyTimeToLive="P5D"></process>`

Refer to the [ASEE Flow documentation regarding case definitions](/user-guide/process-engine/history/history-cleanup) for additional details.

Time to live must be defined under **History cleanup** in the properties panel on the right side of the screen.

### History time to live not configured

<img src="https://mintcdn.com/aseeflow/OpLRJy6TPnBLn55c/modeler/img/history-time-to-live.png?fit=max&auto=format&n=OpLRJy6TPnBLn55c&q=85&s=1a85c36b8ca7826b540da9d44aa949b5" alt="History time to live not configured" width="1300" height="673" data-path="modeler/img/history-time-to-live.png" />

In the screenshot above, note that the time to live must be defined under **History cleanup** in the properties panel on the right side of the screen.

### References

* [History documentation](/user-guide/process-engine/history)
* [Rule source](https://github.com/camunda/bpmnlint-plugin-camunda-compat/blob/main/rules/camunda-platform/history-time-to-live.js)