Creating Asynchronous Image Copies

Asynchronous image copies are the database backups of multiple IMS database data sets that are created in parallel in the same job step for faster processing. The asynchronous process uses the z/OS multitasking function. You can create asynchronous image copies by using
Database Copier
(the IDIDBO program) or its valid alias. The resulting asynchronous image copy represents a database image as of the Change Accumulation end time. The image copy is compatible with the IMS Image copy (DFSUDMP0) and is a valid input to the
High Performance Recovery
and IMS Recovery utility (DFSURDB0).
dmims
Asynchronous image copies are the database backups of multiple IMS database data sets that are created in parallel in the same job step for faster processing. The asynchronous process uses the z/OS multitasking function. You can create asynchronous image copies by using
Database Copier
IDIDBO (the IDIDBO program) or its valid alias. The resulting asynchronous image copy represents a database image as of the Change Accumulation end time. The image copy is compatible with the IMS Image copy (DFSUDMP0) and is a valid input to the
High Performance Recovery
and IMS Recovery utility (DFSURDB0).
To make asynchronous image copies, use the following control statement in your JCL:
FUNCTION=ACOPY,TASKLIMIT=value
or
AIC DBD(dbdname) DDNAME(ddname) TASKLIMIT(number)
Example
The following example demonstrates a request to make five image copies, with four of them made asynchronously in parallel.
  • The DBDs may or may not be unique.
  • The ddnames must be unique within a DBD, but do not need to be unique within the job step.
  • TASKLIMIT keyword, if required, must be specified in the first ACOPY control statement.
Specify in control statements – native syntax:
FUNCTION=ACOPY,DBDNAME=dbd1,DDNAME=ddname1,TASKLIMIT=4 FUNCTION=ACOPY,DBDNAME=dbd2,DDNAME=ddname2 FUNCTION=ACOPY,DBDNAME=dbd3,DDNAME=ddname3 FUNCTION=ACOPY,DBDNAME=dbd4,DDNAME=ddname4 FUNCTION=ACOPY,DBDNAME=dbd5,DDNAME=ddname5
Specify in control statements - compatibility syntax:
AIC DBD(dbdname1) DDN(ddname1) TASKLIMIT(4) AIC DBD(dbdname2) DDN(ddname2) AIC DBD(dbdname3) DDN(ddname3) AIC DBD(dbdname4) DDN(ddname4) AIC DBD(dbdname5) DDN(ddname5)
For a sample JCL for asynchronous image copies, see the member
high-level
.CIMTSAMP(JCLDBC5).
The following conditions apply:
  • Up to 16 image copies can be executed asynchronously.
  • AOIC, AIIC, and ACIC are not supported.
  • Image copies cannot be stacked on one volume, as one volume can be available only to one task at a time.