Hold low priority SIPCC items until 1052 state.

Hold the processing of low priority IPC items until the system reaches 1052 state.

In our loosely-coupled systems, particularly in PSS we had experienced application SIPCC items which come from up and running processors interfering the system IPL. PSS is a 8-way loosley-coupled system. At any given time there are lots of IPC traffic generated by applications.
Application programs activated thru SIPCC attempt to access globals or USAT tables even before they are loaded or initialized. This causes unpredictable errors and interrupts the system IPL.
Let me answer the ffollwoing questions.
1. The application SIPCC's coming from other processors. Are those
generated by the applications themselves or are they from a service the
application is using, like globals?

Answer – they are generated by applications themselves.

2. The PMR mentions the SIPCC's access globals and "some other
tables". Are these IBM tables or HP tables? If they are IBM ones, do
you know which ones?

Answer – they are IBM table (WGTA) and user tables (USAT). For dynamic Norm State Line Fallback we maintain WGTA for all UATs and communicate any updates to WGTA thru SIPCC.

3. It states that HP " cannot IPL a processor due to incoming
application SIPCC items." Is HP literally unable to IPL or is it just
slow?

Answer – we were unable to IPL.