IBM System/370 145 Manual page 16

Additional storage can contribute significantly to system
capabilities and performance. Specifically, the addition of more
processor storage provides the Model 145 user with the ability to:
• Execute more or larger jobs concurrently, including new application
and integrated emulator jobs
• Add and expand applications, such as graphics, teleprocessing, time
sharing, and data base, tha-t require larger amounts of storage
• Use higher leve1 language translators and linkage editors that
provide more functions and execute faster
• Execute larger processing programs without the necessity of overlay
structures
• Allocate more storage to language translators and sorts to improve
their execution speed
• Use more and larger I/O buffers to speed up input/output operations
and optimize use of direct access storage and tape media space
• Include system generation options that improve control program
performance and support additional functions
support of
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Virtual Storage Environment
While the Model 145 has larger processor storage than its comparable-
scale System/360 models, it also provides the capability of implementing
a virtual storage environment, whi'ch allows programmers to write and
execute programs that are larger than the processor storage available to
them. When virtual storage is supported, many of the restraints
normally imposed by the amount of processor storage actually available
in a system are eased. The removal of certain restraints can enable
applications to be installed more easily, and can be valuable in the
installation and operation of online applica"tions. While many of the
new hardware features and I/O devices for the Model 145 and the new
facilities supported by System/310 operating systems are designed to
improve performance, a virtual storage environment is designed primarily
to help improve the productivity of data processing personnel and
enhance the operational flexibility of the installation,.
Greatly Expanded Channel Capabilities
The fast internal performance of the Model 145, together with
expanded use of multiprogramming, requires that more data be available
faster than on the Model 40. A variety of channel options are provided.
Twice the number of byte multiplexer subchannels can be installed on
a Model 145 as on a Model 40. The Model 145 also offers more and faster
high-speed channels than Models 30 and 40, and block multiplexer
channels not provided for these System/360 models. The basic individual
channel data rate of .82 MB can be more than doubled by installation of
the optional Channel Word Buffer feature.
6
The channel features of the Model 145 provide:
• Up to 256 byte multiplexer subchannels for larger teleprocessing
users
• Lower cost direct attachment of 2314A-type disk storage drives via
the new Integrated File Adapter
• Attachment of high-speed direct access devices such as the 3330-
series and 2305 Model 2
A Guide to the IBM Syste11V310 Model 145