Browse Prior Art Database

Single System Image for Distributed Applications Using CICS Multiple Region Operation

IP.com Disclosure Number: IPCOM000100989D
Original Publication Date: 1990-Jun-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 4 page(s) / 140K

Publishing Venue

IBM

Related People

Curtis, DE: AUTHOR [+2]

Abstract

Disclosed is a program for maintaining a single CICS transaction access in an environment where a single transaction code can bring up a menu of applications.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Single System Image for Distributed Applications Using CICS Multiple Region Operation

       Disclosed  is a program for maintaining a single CICS
transaction access in an environment where a single transaction code
can bring up a menu of applications.

      CICS  Multiple Region Operation (MRO) has enabled users to
execute applications and/or application subsystems in separate CICS
regions.  Because each region may be scheduled by MVS on any
available processor, the user's applications ran in parallel.
Typically, this was done through a process known as transaction
routing.  CICS would determine the MRO region by the transaction
code.  As long as the applications could be segregated by transaction
code, CICS MRO could significantly improve performance.  However,
where a single transaction code brings up a menu of applications,
these applications are restricted to a single CICS region.  There is
no existing solution to this problem without reducing the security
and usability of such applications.

      A program, EADPSDXS, called by the command, $DXS, ($DXS stands
for Determine eXecution System) solves the aforementioned problem.
The syntax and operation of this command is:
   $DXS=<application name>
where <application name> is a 1 to 8 character name for the
application.  $DXS will locate which CICS region owns this
application and continue application execution in that region.
  $DXS performs the following steps to do this service:
1.   Uses a new table, ACARSYS, to associate the <application name>
with a particular CICS region.  This table contains the following
essential information:
      a.   The <application name>.
      b.   The CICS system name which owns the application.
      c.   The CICS transaction code which will transaction route
processing to the owning region.
2.   If MRO support is not active or the current region already owns
the application, the $DXS command does nothing.
3.   If MRO support is active and the current region does not own the
application, the $DXS command saves the Symbol Table and Command
Stack in the target MRO region using CICS function shipping,
schedules a restart of the application in the target region using
SINGLE CICS transaction routing a...