Observed in a thread dump:
"Running CpsFlowExecution[Owner[.../...:... #...]]" id=... state=WAITING cpu=70%
- waiting on <0x...> (a com.google.common.util.concurrent.AbstractFuture$Sync)
- locked <0x...> (a com.google.common.util.concurrent.AbstractFuture$Sync)
at sun.misc.Unsafe.park(Native Method)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304)
at com.google.common.util.concurrent.AbstractFuture$Sync.get(AbstractFuture.java:275)
at com.google.common.util.concurrent.AbstractFuture.get(AbstractFuture.java:111)
at org.jenkinsci.plugins.workflow.support.steps.input.InputAction.loadExecutions(InputAction.java:69)
at org.jenkinsci.plugins.workflow.support.steps.input.InputAction.remove(InputAction.java:141)
- locked org.jenkinsci.plugins.workflow.support.steps.input.InputAction@4f8d2160
at org.jenkinsci.plugins.workflow.support.steps.input.InputStepExecution.postSettlement(InputStepExecution.java:222)
at org.jenkinsci.plugins.workflow.support.steps.input.InputStepExecution.doAbort(InputStepExecution.java:191)
at org.jenkinsci.plugins.workflow.support.steps.input.InputStepExecution.stop(InputStepExecution.java:80)
at org.jenkinsci.plugins.workflow.cps.CpsBodyExecution$1.onSuccess(CpsBodyExecution.java:210)
at org.jenkinsci.plugins.workflow.cps.CpsBodyExecution$1.onSuccess(CpsBodyExecution.java:199)
at org.jenkinsci.plugins.workflow.cps.CpsFlowExecution$4$1.run(CpsFlowExecution.java:568)
at ...
InputAction.loadExecutions currently needs to use a weak API which forces it to block. See discussion here.