What is the Process Simulation?
In SAP Signavio Process Manager the Process Simulation is a dedicated feature that uses typical process metrics to deliver insights on:
- What-if scenarios
- Process behavior
- Resource planning and optimization
- Average costs and times
- Peaks and bottlenecks
Why are process simulations applied in general?
- To improve existing operations and evaluate new plans and alternatives
- To avoid time-consuming fine-tuning and expensive testings
- To reduce cycle times, idle times and localize weak points and bottlenecks
- To evaluate alternative concepts, modified process variants and capacity expansion
The BPMN simulation tool allows you to visualize process runs and to analyze processes based on configurable one-case and multiple-case scenarios in order to gain information about cost, cycle times, resources and bottlenecks. Have a look on the simulation in practice!
Setting Up Simulation Parameters
Simulating Business Processes can answer typical questions and help to make more well-informed decisions. In this case we will investigate a simple Order-to-Cash process.
Managing Activity Costs
Typical requirement: "How much money would a small decrease in shipment cost save us?"
Activity costs need to be provided in order to calculate the overall process costs. These granular costs might include material, electricity and other task specific expenses. Labor costs are set up under Resources.
The currency can be configured in the settings.
Managing Execution Times
Typical requirement: "How would a reduced shipment duration influence the total cycle time?"
Execution times for tasks are needed to calculate the (minimum) total cycle time of a process.
In practice the cycle time is more than just the sum of time for all task executions. Often, there are also waiting times, idle times and many more to consider which might have an impact on the process.
The simulation focuses mainly on task execution times to calculate the minimum cycle time of a process.
Whenever tasks are performed by employees, it's just natural that the execution time is always different. For this reason, it might be helpful to consider deviations for manual tasks.
In our example we used a normal distribution around the mean execution time to reflect this.
Optional: Consider a deviation in your execution times for tasks
Managing Process Frequency
Typical requirement: "Can we manage a 40% increase of our order volume ?"
To simulate multiple cases, the amount of cases starting during a week need to be set up in the Frequency tab.
The number of cases can be adjusted to accommodate peaks and valleys in the workload depending on the day of the week and time of the day.
Each decision point where the process might take different routes has to be configured with an estimation of the respective outcome probabilities.
Every time a case reaches these points the given values will be used independently of previous cases to route the process.
Each decision gateway has a probability field in the Frequency tab.
Managing Working Schedules
Typical requirement: "Can we keep up with the order volume in case of illness-related absences ?"
The available resources are the most important factor influencing the total cycle time and bottlenecks.
Resources can be set up with detailed working schedules and hourly wages which will be used to calculate the overall process costs.
Edit working schedules for each lane in the Resource tab.
Troubleshoot - Interpreting Simulation Results
The metrics of the results of a multiple-case simulation.
Results - Costs – The overall process costs are the sum of fixed activity costs and resource costs. They may vary depending on the execution time if deviations for activity times are used.
Results - Total cycle time –The total cycle time is the sum of all execution and waiting times. Long maximum times usually indicate a bottleneck in the respective lane causing long waiting times due to a lack of resources. The total cycle time can exceed the simulation time span. This may happen for two reasons:
- Your resources can't handle cases fast enough and process instances 'pile up'.
- The cases that occur in the last hours/minutes of your simulation time frame exceed the frame before they are completed.
Results - Resource consumption – The resource consumption table shows how much of their work time the process participants need to spend on the simulated process.
Results - Bottlenecks – In the bottleneck tab the pure waiting times are listed on an activity level. This can give an indication where the process needs to be adjusted or more employees are required.
Simulation Run Example
A bottleneck occurs when a resource's limited availability increases the waiting times of cases. As soon as a new case started the resource was still handling a previously started instance. Adding additional resources for both resources might reduce waiting times and cycle times.