Parallel processing in Pega

We can allow users to perform multiple tasks independently to complete the work, in pega we can this as parallel processing. In a stage or flow rule, we can add smart shapes to achieve this parallel processing.

Smart shapes in pega

Pega has defined some smart shapes like Split Join, Split-For-Each, and Spin-Off. We have to use these smart shapes in sub-process shape. Each shape can call one or more processes to proceed in parallel.

Spin-Off in pega

The spinoff is not a shape, it is an option in the sub-process shape. Which allows running the sub-process independent and in parallel to the main process. The main flow will not wait for the sub-process and no join options available for SpinOff processes.

How to configure Spin-Off option in a subprocess

I Will explain with an example: In a Service Request case type when the user submits a request it should be going for the inspection process. Used Split Join shape to fulfill this requirement with two sub-processes. When all sub-processes are complete, the main Service Request application process can continue to the Review stage where the management team will review the inspection report. In the Review stage, the Inspection report will be reviewed and approved by various Reviewers. To fulfill this requirement we are using Split For Each shape and providing Reviewer details in a PageList. Pega will use this PageList and iterate the process. Once the review is completed the technical team will repair the issue. In the Resolution, stage initiating "Generate Documents" sub-process as an independent parallel process. Service Request case will proceed further and resolve without waiting for the SpinOff process (Generate Documents).

let's create a case and see the process.

The main flow for Service Request continues without waiting for the spinOff sub-flow (GenerateDocs).

If you want to invoke an independent flow in parallel with the main flow and without stopping the main process we can go for the spin-off option in the sub-process.

Related topics in parallel processing:

Split Join shape in pega

Split For Each shape in pega

Comparing the three parallel options

	Split-Join	Split-For-Each	Spin-Off
Starts	Two or more different flows	One flow, once for each item in a page list or group	One flow, running on its own
Main flow waits?	Yes, until the join condition is met (Any or All)	Yes, with Any, All or Iterate	No. It carries on immediately
Join options	Yes	Yes	None
Typical use	Two teams approve at the same time	Every reviewer or work party must respond	Send a notification or log an audit task without holding the case

When to choose Spin-Off

The extra work does not affect the main flow's next step.
You do not need to know when, or whether, it finished before the case moves on.
Examples: an email reminder, a compliance record, a request to archive documents.

A worked example

In a bank's Loan case, when the application is approved, the main flow moves straight to Fulfilment. At the same moment a Spin-Off starts a subprocess that sends the customer a welcome pack and creates a marketing follow-up task. If the welcome pack fails, the loan is not held up, and the error is dealt with by whoever owns that subprocess.

Cautions

Because nothing waits for a Spin-Off, do not use it for work the case depends on. Use Split-Join instead.
Give spun-off work a clear owner and a service level, or it can be forgotten.
A parent case that resolves before its spun-off work finishes needs a rule for what happens to the child work.

Related: Split-Join, Split-For-Each and Spin-Off and the Case Management label.

Spin Off in pega