IBM System/370 145 Manual page 168

SECTION 40: EMULATORS
40:05 OS 1410/1010 AND 1401/1440/1460 EMULATOR PROGRAMS
FEATURES COMMON TO BOTH EMULATORS
One of the significant new features of the Model 145 for OS users is
support of integrated 1400/1010-series emulation. Only stand-alone
1400/7010 emulation is available to Model 30 and 40 OS users. A
1410/7010 Emulator program and a 1401/1440/1460 Emulator program that
operate under OS control on the Model 145 are provided. These emulators
operate under OS MFT, MVT, VS1, and VS2.
An emulator program requires the presence of either the IBM
1401/1440/1460 Compatibility or the 1401/40/60, 1410/7010 Compatibility
feature. These no-charge options are the same features used by the two
integrated DOS 1400/7010 emulator programs for the Model 145. The
latter feature permits operation of both the 1401/1440/1460 emulator and
the 1410/7010 emulator.
The OS 1401/1440/1460 emulator for the Model 145 provides the same
functions as the OS 1401/1440/1460 emulators for System/370 Models 135
and 155. This is also true of the 1410/1010 emulators for Models 145
and 155. The 1401/1440/1460 compatibility features on Models 145 and
135 are identical but the 1400/7010 compatibility features on Models 145
and 155 differ slightly in their implementation (for SAR and SBR
instructions). Therefore, a 1401/1440/1460 emulator program generated
for the Model 145 will run on a Model 135 but not on a Model 155, nor
will a 1410/7010 emulator generated for the Model 145 Iun on a Model
155. However a 1400/7010 emulator program generated for the Model 155
will run on Models 135 (1401/1440/1460 only) and 145.
The emulators operate as processing programs in MFT and MVT
environments and are alike in their functional design. Those features
common to both are discussed first.
The 1400/1010 emulator programs supplied for the Model 145 are
relocatable and thus can operate in one or more
MFT
partitions or MVT
regions. Any number of emulator jobs of the same or different types
(1401, 1440, 1460, 1410, and 1010) can execute concurrently with
System/370 jobs in the same Model 145, subject to the availability of
system resources. Emulator and System/370 jobs can be intermixed in the
input stream
w
since emulator job scheduling, initiation, and resource
allocation are handled by OS job management routines. I/O operations
are handled by OS data management. Emulator jobs are executed by job
priority as is any OS job.
Integrated emulation provides a number of advantages over stand-alone
emulation that can increase system throughput. The ability to execute
1400/7010-series jobs under operating system control offers emulation
users the benefits of multiprogramming and OS facilities. The
advantages of Model 145 integrated emulation are:
• Significantly better resource utilization, since system/370 native
mode and 1400/1010-series emulator jobs can be multiprogrammed.
Stand-alone emulators normally use only a portion of the hardware
resources available in the system •
• Standardized and simplified job accounting and job scheduling. The
latter reduces the number of IPL's required because switching from
158 A Guide to the IBM system/31 0 Model 145