Job queue
Every time you invoke a function, Quapp creates a job and places it in the queue for the device you selected. This page explains the states a job passes through and why a job may wait before it runs.
Job lifecycle
A job moves through the following states:
| State | Meaning |
|---|---|
| Queued | The job has been accepted and is waiting for the selected device to become available. |
| Running | The device is executing the job. |
| Done | Execution finished successfully and the results are available. |
| Error | Execution failed. Open the job to see the error details. |
Queued → Running → Done is the normal path. A job that fails ends in Error instead of Done.
Why a job stays Queued
A job waits in Queued until its device is free. How long that takes depends on the device you chose:
- Simulators usually start almost immediately.
- QPUs (real quantum hardware) are shared resources with their own queues and availability windows. A long wait in Queued is normal and does not mean the job has failed.
You can check device availability before invoking a function — see Provider's Devices.
Tracking a queued job
Open the job from the Related Jobs section of the function, or from the provider's job list, to see its current state. Use Refresh on the Job Details page to update the status and result data.
For everything the Job Details page shows, see Managing and Tracking Job Results.