Aftger reviewed the dump for the stalled collection task 12 for the DI2C Detector collection and the stalled collection task for the DI1C Detector collection task. It appears to be a dispatching issue. There was no evidence of a loop.
The Xmanager XMAN4E address spaces dispatching priority is set to X’F0’ the DI1C and DI2C address spaces are set to x’F8’. The Xmanager dispatching priority needs to have a dispatching priority the same or higher than the DB2 address spaces. This is especially true when using the Detector collection tasks.
The CDBAPARM collection tasks are set up to run on a zIIP. The dump shows that the zIIPs utilization is 100% and the general purpose CPUs are at 66%. The IEAOPT parameters appear to be set to allow the collection task to fall back and run on a CPU but that did not occur in a timely manner. The work dispatched on the zIIPs is probably a higher dispatching priority than the Xmanager address space.
The recommendation is to increase the dispatching priority of the Xmanager address space to be the same or higher than the DB2 address spaces.