r
Problem
Type Where Abend Occurs Distinguishing Characteristics Wait IDisabled RSCS IIf a program check occurs after the program (cont.) I wait (cont.) I check handler is activated, RSCS enters a
Loop I disabled wait state with a code of 001 in the PSi. One of the following messages may also appear on the RSCS console: DMTREX090T PROGRAM CHECK IN SUPERVISOR RSCS SHUTDOWN DMTREX091T INITIALIZATION FAILURE -- RSCS SHUTDOWN Enabled RSCS IRSCS has no task ready for execution. A
wait I PSW, for external and I/O CP disabled
loop I interrupts, is loaded with a wait code of
i all zeros. IThe processor console wait light is The I problem state bit of the real PSi is off. I No I/O interrupts are accepted. IThe program is taking longer to execute than I anticipated. Signaling attention from the Virtual machine
disabled loopl terminal does not cause an interrupt in the I virtual The virtual machine opera­ I tor cannot communicate with the virtual Virtual machine
enabled loop I machine's operating system by signalling I attention. IExcessive processing time is often an indi­ I cation of a loop_ Use the CP QUERY TIME I command to check the elapsed processing I time. In CMS, the continued typing of the I blip characters indicates that processing I time is elapsing. If time has elapsed, I periodically display the virtual PSi and I check the instruction address. If the same
1 instruction, or series of instructions, I continues to appear in the PSi, a loop I probably Figure VM/370 Problem Types (Part 6 of 6)
ANALYZING THE PROBLEM Once the type of problem is identified, its cause must be determined.
There are recommended procedures to follow. These procedures are
helpful, but do not identify the cause of the Froblem in every case. fe resourceful. Use whatever data you have available. If the cause of the
problem is not found after the recommended debugging procedures are
followed, it may be necessary to undertake the tedious job of
desk-checking.
The section "How To Use VM/370 Facilities To Debug" describes
procedures to follow in determining the cause of various problems that
can occur in the Control Program or in the virtual machine. See the VM/370 £MS for information on using VM/370 facilities to
debug a problem program.
Part 1. Debugging with VM/370 13

If it becomes necessary to apply a program Temporary Fix (PTF) to a YM/370 component, refer to the gDQ Generation for detailed information on applying PTFs. Figure 3. -Plgure-4; and Figure 5 summarize the debugging process from identifying the
problem to finding the cause. 14 IEM iM/370 System Programmerls Guide