IBM S/390 Reference Manual page 24

Scalar square root.
Two instructions for short and long precision square root.
SIE assist.
In VM environments, provides most I/O without control
program intervention for dedicated devices of preferred
guests, offering improved performance.
Subspace Group Facility.
Protects CICS application programs within the same
address space from accidentally or intentionally over-
laying each others' code or data. This facility is also
know as Transaction Isolation, and augments the Sub-
system Storage Protection feature that is used by CICS
to prevent application programs from overlaying CICS
system code and data.
Subsystem Storage Protection Facility.
Enables CICS/ESA to provide its storage protection func-
tion, which reduces CICS/ESA system failures, increases
user productivity, and reduces system management
effort required for certain types of problem diagnosis.
Support element.
A hardware unit that provides communications, monitor-
ing and diagnostic functions to a central electronic
complex (CEC).
Suppression on Protection.
This hardware facility can improve performance in the
™
z/OS, OS/390, MVS/ESA
environments (MVS/ESA support is in V5.2.2). The ben-
®
efit applies to UNIX fork( ) processing. The fork( )
operation creates a copy of the issuing program which
will execute independently. The Suppression on Protec-
tion facility allows the new child process to share the
parent process pages on a read-only basis; new copies
of pages are made only when the system detects that
the child is attempting to modify one of the shared pages.
(Note that AIX/ESA is not supported on the 9672 processor.)
44
®
OpenEdition and AIX/ESA
Uniprocessor (UP).
A CEC that contains one central processor.
VM/ESA (Virtual Machine/Enterprise Systems Architecture).
A high-performance, interactive operating system for
IBM S/390 processors. VM/ESA provides support for
guest operating systems and client/server and network
computing environments, allowing you to integrate your
information processing resources for maximum reach
and range.
VSE/ESA (Virtual Storage Extended/Enterprise Systems
Architecture).
Entry and intermediate S/390 operating system package
with full function batch and online transaction process-
ing. The S/390 operating system of choice for multiple or
centrally managed, remote unattended systems.
z/VM
z/VM is an operating system based on the new 64-bit
z/Architecture. z/VM provides a highly flexible test and
production environment for enterprises deploying the lat-
est e-business solutions. Built upon the solid VM/ESA
base, z/VM exploits the z/Architecture and helps enter-
prises meet their growing demands for multi-user server
solutions with a broad range of support for operating sys-
tem environments such as z/OS, OS/390, TPF, VSE/ESA,
CMS, Linux for S/390 or Linux for zSeries.
z/OS
®
z/OS is a robust operating system that is based on the new
64-bit z/Architecture. It delivers the highest qualities of ser-
vice for enterprise transactions and data, and extends
these qualities to new applications using the latest software
technologies. It provides a highly secure, scalable, high-
performance base on which to build and deploy Internet
and Java enabled applications, providing a comprehen-
sive and diverse application execution environment.
49
45