Paqe of GC20-1807-7 As Updated April 1, 1981 by TNL GN2S-0829 r------ , Messaqe I I DMKMCH612W MACHINE CHECK; TIMING I FACILITIES DAMAGE; RUN SEREP I , I DMKMcr620I MACHINE CHECK; ATTACHED I PROCESSOR NOT BEING USED DMKCCH603W CHANNEL ERROR, RUN SEREP,
RESTART SYSTEM DMKCPI955W INSUFFICIENT STORAGE FOR VM/370 DMKMCH622W MACHINE CHECK; MULTIPLE CHANNEL ERRORS DMSABN148T SYSTEM ABEND xxx
CALLED FROM xxxxxx Others Refer to OS and DOS publications
for the abnormal termination
messages.
Type of Abend I --------I An error has occurred in the I timing facilities. Probable I hard error. I A malfunction alert, clock
clock error or instruction
processing error occurred on
the attached processor.
The system continues to run
in uniprocessor mode.
CP termination without auto­
matic restart.
There was a channel check
condition from which the
channel check handler could
not recover. CP enters the
wait state with code 002 in I the Psw. IThe generated system requires I more real storage than is I available. CP enters the I disabled wait state with I code OOD in the PSW. IThere was a group error I machine check from which the I machine check handler could I not recover. CP enters a I wait state with code 001 in 1 in the PSW. I I ,eMS abend, system will acceptl
commands from the terminal. I Enter the DEBUG command and I then the DUMP subcommand to 1
have CMS dump storage on thel printer. I I IWhen OS or DOS abnormally I I terminates on a virtual I t machine, the messages issuedl I and the dumps taken are the 1 I same as they would be if OS I I or DOS abnormally terminatedl I on a real machine. I L­ ______________________________________________________-J
Fiqure 1. Abend Messages (Part 3 of 3)
Another obvious indication of a problem is unexpected output. If your
output is missinq, incorrect, or in a different format than expected,
some problem exists. Unproductive processing
problem is not as easily
environment.
time is another symptom of a
recognized, especially in a
6 IBM VM/370 System proqrammer's Guide
problem. This
time-sharing

IDENTIFYING THE PROBLEM Two types of problems are eas1lY identified: abnormal termination is
indicated by an error message, and unexpected results become apparent onoe the output is examined. The looping and wait state conditions are not as easily identified. When using VM/370, you are nor.ally sitting at a terminal and do not
have the lights of the processor control panel to help you. You may have
a looping condition if your program takes longer to execute than you
anticipated. Also, check your output. If the number of output records or
print lines is greater than expected, the output may really be the same
information repeated many times. Repetitive output usually indicates a
program loop_ Another way to identify a loop is to periodically examine the current If the PSW instruction address always has the same value, or if the
instruction address has a series of repeating values, the program
probably is looping. The wait state is also difficult to recognize when at the terminal.
Again, the console lights are If your program is taking
longer than expected to execute, the virtual machine may be in a wait state. Display the current PSW on the terminal. Periodically, issue the CP command QUERY TIME and compare the elapsed processing time. When the elapsed processing
time does not increase, the wait state probably exists.
Figure 2 helps you to identify problem types and the areas where they may occur. Part 1. Debugging with VM/370 7