Timers in process flows: interruptive and non-interruptive

Timers are tools that allow you to incorporate time-based conditions into an active User Task. They work like a combination of a stopwatch and an alarm clock: when a task with a timer is reached, it starts counting, and once the configured interval is met, a specific action is triggered.

Depending on the type of timer, two things can happen:

• With an interrupting timer, the linked task is interrupted and the flow continues through an alternative path.
• With a non-interrupting timer, the main task remains active, and an additional execution is triggered through another process path.

Here we explain the differences, when to use each one, how to configure them, and practical examples.

When to Use Each Type

• Use an interrupting timer when you want the process to automatically proceed through an alternative path if the task is not completed within the specified time. For example, if someone must review a request within 3 days, and if they don’t, it should be automatically sent to a supervisor or rejected.

• Use a non-interrupting timer when you want to trigger complementary actions (reminders, alerts, follow-ups) without preventing the main task from remaining active. For example, sending a reminder email to the user if they haven’t acted within 24 hours, but still allowing them to continue working on the task.

How to Add a Timer

To add a timer, simply drag the element and connect it to a User Task. By default, the timer will be configured as interrupting. We'll explain how to change its type below.

Configuring an Interrupting Timer

1. Once added, double-click on the timer to define the time frame (you can combine years, months, days, hours, minutes, seconds), set a duration based on your working days configuration, or use an absolute date based on a date-type field.

2. Set the alternative path that should be executed when the timer expires (i.e., if the task is not completed in time).

Behavior: if the user does not complete the task before the deadline, that task is canceled and the flow continues exclusively through the timer path.

Configuring a Non-Interrupting Timer

1. When you add a timer, it will appear as interrupting by default. Click on the timer, select the settings option (wrench icon), and switch it to non-interrupting.

2. Double-click on the timer to define the time frame (you can combine years, months, days, hours, minutes, seconds), set a duration based on your working days configuration, or use an absolute date based on a date-type field.

3. Configure the parallel path that the workflow should follow when the timer expires.

Behavior: if the user does not complete the task in time, the timer triggers the alternative path without canceling the original task. Both paths (the user's and the timer's) can coexist.

Recurring Executions

You can configure non-interrupting timers to execute repeatedly until their associated User Task is completed.

To do this, configure the Number of executions field with the maximum number of times you want the timer to be triggered.

This is useful for sending recurring reminders while the task remains active.

Behavior: each time the timer is triggered, it will restart the configured time interval, after which a new execution will be triggered.

Loop Execution and Potential Issues

When configuring non-interrupting timers, you must be especially careful not to create loop executions like the following:

If the parallel flow is connected back to the User Task, a new copy of the process instance will be created each time the timer is triggered.

Disconnect the additional flow from the user task to ensure the paths remain independent.

Practical Examples

Example of an Interrupting Timer: Review Expiration

Let’s say that in an approval process, there is a "Review Request" task with a 3-day deadline. If the review is not completed in that time, you want the request to automatically go to the manager.

• You place an interrupting timer linked to that task, with a 3-day deadline.
• Define the alternative path: “Manager Review.”
• If the user reviews the request before the 3 days, the flow continues normally.
• If not, the “Review Request” task is canceled and the flow follows the “Manager Review” path.

Example of a Non-Interrupting Timer: Pending Task Reminder

Imagine a process where a “Complete Report” task must be done within 5 days. You want to send the user a reminder 2 days before the deadline if it hasn’t been completed yet, but still allow them to continue working.

• Add a non-interrupting timer linked to the task, with a 3-day deadline (or equivalent, depending on when you want the reminder).
• Define a parallel path that sends a reminder email.
• If the user completes the report before the 3 days, the reminder has no effect.
• The “Complete Report” task remains active throughout the 5 days, or until completed.
• You can add more than one non-interrupting timer: for example, one for reminders that executes every 1 day (for 5 days), and another one that runs once after the 5-day period to notify the Supervisor. Just be careful to avoid duplicates or infinite loops.

Best Practices and Recommendations

• Don’t mix interrupting timers: a task cannot have more than one, and it’s not recommended — only one will be triggered.
• Limit the use of non-interrupting timers: while you can have several per task, each path must make sense and avoid unwanted loops.
• Avoid loops or duplications: especially with non-interrupting timers triggering actions that reactivate the same task or process instances.
• Clearly document alternative paths: when designing the flow, ensure each timer has a well-defined route that doesn’t cause ambiguity with the main path.
• Use absolute dates carefully: when the timer depends on a date-type field, ensure that the field is always available and contains a valid value (a date later than the assignment day), otherwise the timer may trigger immediately.

Updated on: 30/09/2025