Factors affecting user experience

Background processing benefits user experience and productivity. When possible, run the required processing in the background, so that the end user does not have to wait for it to complete. This area is also referred to as asynchronous processing. While the user is busy reading a screen or completing another task, the application performs required tasks in another requestor session, apart from the requestor session of the user.

Scenarios where background processing can be leveraged include:

• SOR pattern
• External integration
• Network latency

When leveraging the SOR pattern, required data is not kept with the case itself. Instead, the data is retrieved when needed at runtime from an external SOR. In these scenarios, you can defer the load of the external data after the initial screen is loaded.

External integration with an SOR is almost always a requirement. When integrating with external systems, establish realistic expectations on the time that is needed to load data retrieved from the external systems. By leveraging background processing and asynchronous processing, you can quickly render an initial user interface. This technique allows the end user to start working while the application gathers additional data. The application then displays the data as soon as it becomes available.

Never underestimate the impact that network latency can have on the amount of time required to retrieve data from external systems. Whenever possible, colocate the Pega database repository on the same high-speed network as the application servers running the Pega Platform™ or engine. Keep systems that you are integrating with as close as possible to your data center. If the system that you are integrating with is located very far away, consider using replicated data from a nearby data warehouse or proxy system. You can also use Edge Servers for web content that is referenced frequently.

When it comes to data, less is always better. Avoid retrieving large data sets. Keep your result sets as small as possible. Only retrieve the data that is immediately required for the task at hand. Consider aggregating data sets ahead of time by introducing data warehouses and multidimensional databases where quick response times are critical.

If it takes longer than a couple of seconds to load a screen, provide the end user with meaningful feedback on how much time is needed to complete the processing. Give the end user something else to do while the processing is taking place. You can also design the interaction to opt to perform it in the background or cancel out if it takes too long. Always keep the end user in control.

As the form factor changes, leverage the responsive UI support of Pega Platform and show the user only what is necessary to complete the task at hand. Avoid creating the "Everything View" that tries to deliver every piece of information all at once. Move unnecessary or optional information away from the screen as the screen size is reduced. Keep your user interfaces highly specialized and focused on individual and specific tasks.

Many application performance issues affect the user experience directly or indirectly. Because the application shares resources across users and background processes, an issue in another part of the application can affect the individual end user somehow.

Sometimes, performance issues show up only after the application has been in production for several weeks and users over a period of days start to experience performance degradation. Use performance tools and troubleshooting techniques to identify the causes of poor performance. For more information, see Troubleshooting techniques.