# PRESTREAM

A Prestream can be utilized with specific IO profiles. When a profile is triggered, the Prestream can execute a workflow in advance. A Prestream streamcan only be added to anothe profile, there is no dedicated Prestream Profile available.

Any information collected or gathered (e.g., stream variables) during its runtime will be passed on to the actual stream of the triggering origin.

It is possible to cancel a job by employing a [Job Status Update Action](/helmut4-releases/helmut4-components/streamdesigner/nodes/actions/job-action/job-status-update-action.md) node or a [Job Delete Action](/helmut4-releases/helmut4-components/streamdesigner/nodes/actions/job-action/job-delete-action.md) node. 

Another functionality of the Prestream is that the job can be reassigned to another client by using a [Job Create Job Action](/helmut4-releases/helmut4-components/streamdesigner/nodes/actions/job-action/job-create-job-action.md) node followed by a [Job Delete Action](/helmut4-releases/helmut4-components/streamdesigner/nodes/actions/job-action/job-delete-action.md) node. Please keep in mind that this cannot be used to recall the same profile, as the Prestream would end up in a loop. Instead, the target stream should be utilized in another profile without a dedicated Prestream.

{% hint style="warning" %}
**Disclaimer:**\
Pre-streams are designed to perform quick checks or verifications that typically last only a few milliseconds, or at most a few seconds. If a pre-stream is implemented in a way that takes around 20 seconds, it can significantly stall the job queue.
{% endhint %}

### Host Assignment

{% hint style="warning" %}
Any stream with this trigger must have "CLIENT" as the host type.

Since this stream needs to be assigned to any user/client, server execution is not possible.
{% endhint %}

###  Limitation

{% hint style="danger" %}
Using a [Split Stream Action](/helmut4-releases/helmut4-components/streamdesigner/nodes/actions/misc-21/split-stream-action.md) node within a Prestream is not permitted.

A Prestream can only have synchronous execution, meaning that the stream runtime cannot exceed 60 seconds.
{% endhint %}


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