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Hung thread in PRClassloaderDB and VirtualTableCandidate



Post JVM restart, all Service Packages throw 'Timed out borrowing service requestor from requestor pool for service package' and the App requestors never return to the pool. Agent debug shows them all as busy and thread dumps show WebContainer and MQ threads locked up for hours and a deadlock is detected involving PRClassLoaderDB.

Error Messages

[**Date Time Timezone**] 000000b0 ThreadMonitor W WSVR0605W: Thread "WebContainer : 0" (00000198) has been active for 730225 milliseconds and may be hung. There is/are 1 thread(s) in total in the server that may be hung.
at sun.misc.Unsafe.park(Native Method)
at java.util.concurrent.locks.LockSupport.park(
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(

Steps to Reproduce

There is no specific use case to replicate this issue.

Root Cause

A defect in Pegasystems’ code or rules.


Apply HFix-27551.

Published May 14, 2016 - Updated October 8, 2020

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