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Support Article

StackOverflowError and harness creation is failing



After upgrading to Pega 7.2.2 from Pega 7.1.7 developer is not able to create a new Harness rule or do "save as " of existing harness rules.
In the rule form after clicking Save button the rule is not created and no error message is thrown on the screen.

Error Messages

The following error appears in the PegaRULES log file :- PRRuntimeError
at com.pega.pegarules.session.internal.mgmt.base.ThreadRunner.runActivitiesAlt(
at com.pega.pegarules.session.internal.mgmt.PRThreadImpl.runActivitiesAlt(
at com.pega.pegarules.session.internal.engineinterface.service.HttpAPI.runActivities(
at com.pega.pegarules.session.external.engineinterface.service.EngineAPI.processRequestInner(

Caused by: java.lang.StackOverflowError
at java.util.regex.Pattern$BranchConn.match(
at java.util.regex.Pattern$Curly.match1(
at java.util.regex.Pattern$Curly.match(
at java.util.regex.Pattern$Branch.match(
at java.util.regex.Pattern$GroupHead.match(
at java.util.regex.Pattern$LazyLoop.match(
at java.util.regex.Pattern$GroupTail.match(

Steps to Reproduce

Create a new harness or 'save as' an existing harness.

Root Cause

As seen in the PegaRULES log the issue happened due to stackoverflow that reflects the JVM stack size for the Pega application server is not sufficiently set.


Increase the JVM stack size with the -Xss40m Java argument.

Published July 6, 2017 - Updated October 8, 2020

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