I 1 '-I I I I I SET I SET I SET I SET I ISASSIST ON ISASSIST ON ISASSIST OFF I SASSIST OFF I V!/370 I SET I SET I SET I SET IHardware Assist ICPASSIST OFFICPASSIST ON ICP1SSIST ON ICP1SSIST OFF I I I I I iiirtual Machine v • V I I A I A I , I Assist I I I I • I I I I .. IVirtual Intervall X I X I I I I Timer Assist I I I I I • I I I I I IExtended virtual I I X I I I I !achine Assist I I I I I • I I I I I ICP Assist I I X I I I , f f f • I I , , • I .. ILegend: X = function activated I I Figure 3. Command Control of V!/370 Hardware Assist A virtual machine running in certain virtual machine modes or running
certain operations cannot use certain facilities provided by Vft/370 hardware assist. When these modes or operations are encountered, the
action taken is dependent upon the processor facilities of either
virtual machine assist or V!/370 Extended Control-program Support.
For all V!/310 supported processors that have V!/370 hardware assist
active when the CP ADSTOP or certain CP TRACE command functions are
encountered, the virtual machine assist is deactivated during the
interval of their use.
For System/310 Models 135-3, 138, 145-3, and 148, the use of the DOS emulator or PER (prograa Event Recording) curtails some of the function
provided by VM/370 Extended Control-Program SUPFort. For aore details
on VM/310 hardware assist, see the §Yide. AFFINITY In Attached Processor systems a virtual aachine aay be designated to
execute only on one specified processor. This may be advantageous for
performance or functional requirements. Performance gains might be
realized with affinity because of the nature of the workload or the
availability of performance assists on one processor. Functional
requirements could be the existence of required operation codes on one
processor. In either case, CP code executed on behalf of the virtual machine aay execute on either processor. 34 'M/370 Operator;s Guide

Page of GC20-1806-9 As Updated April 1, 1981 by TNL GN25-0834 System Termination
The VK/370 system be shut down in one of two ways:
1. By an operator initiated shutdown.
2. By an abnormal termination of operation.
The normal shutdown is initiated by a class 1 operator entering the
command "shu tdown" from the operator's console. If the SHUTDOWN command is ineffective,
press the LOAD button on the system console once to shut down the system
(a second pressing of the load button reloads The shutdown operation and accounting functions;
in user is terminated by automatically logging off
all virtual aachines and communication lines. Open and active
files on the spool unit record devices are purged and, if applicable the SUSPEN'D order is issued to all 3851 device addresses (suspends Kes interface activity to the host virtual Note that the SUSPEND order issued to a Kass Storage Control interface may cause the SHUTDOWN co.mand to run longer than usual. !Qte: Before issuing the SHUTDOWN command, a message or warning should
be sent to all logged-on users so that they can quickly bring their
virtual machines t.o an orderly halt. Time should also be allotted to
the class D (spooling) operator so that he too can terminate in an
orderly manner the active files being processed on the unit record
devices.
The dump unit for V8/310 system failures is specified in the SYSDUKP macro during V8/370 system generation, but can be changed by a privilege
class A or class B system operator.
If the dump unit is set to disk (b' default or via the SET DU8P AUTO command) at the time of system failure, the, system dumps all or parts of
real storage to the specified disk and automatically restarts the V8/370 system. When automatically restarted, the system preserves all accounting
information and spool file data on disk, performs an automatic logon of
the primary system operator, restores the system LOGMSG, and continues
system operation. It is not necessary to re-enable the lines, since dump and re-IPL automatically re-enable them. The V8/370 online message is sent to the terminal users, indicating that they must log on again. If, at the time of the system failure, the dump unit is set to a
printer or tape, the V8/370 system writes the dump on the specified
unit, preserves the spooling and accounting data, and stops. The
operator must then re-IPL the V8/370 system as for normal system start
up, specifying a WARM START to preserve the accounting and spooling file data. The operator must re-enahle the communication lines to permit
users to log on again.
Note: An abnormal termination of an attached processor configuration is by the same conditions that cause abnormal termination of a
uniprocessor configuration (uncorrectable hardware error, program check
during the execution of CP, CP issues abnormal termination request
because of logical processing errors, or the primary system operator
initiates a SYSTEK RESTART). Section 2. Initiating V8/370 Operation 35