Concurrent analysis

Concurrent analysis operating characteristics are as follows:

• The DEDB is online during analysis.

• Read-without-integrity access is used.

• Unprotected updates can occur during analysis.

• Performance of the online IMS system is not affected.

During concurrent analysis, the DEDB might be under the active control of an IMS online control region, but IMS services are not used to read the area. If updates occur during analysis, the analysis function might report transient errors as a result of analysis and update lag time. Running a concurrent analysis again probably will not report the same errors. Subsequent concurrent analysis runs can help determine whether any reported errors resulted from such transient conditions.

Inputs and outputs for the concurrent analysis function

The following figure shows the inputs and outputs for the concurrent analysis function.

Control statement (ACCESS=CONCURRENT)

To perform concurrent analysis of a DEDB, you must specify the ACCESS=CONCURRENT keyword. DBRC must also be active during this analysis.

In this example, the area data set, ACB library, and RECON data sets are accessed by using dynamic allocation. Analysis is limited only to the area that is specified with the IAREA keyword.

Example JCL for a concurrent analysis

//ANALYZE  EXEC PGM=PFPMAIN,REGION=0M
//STEPLIB  DD   DSN=BMC.PFP.LOAD,DISP=SHR
//         DD   DSN=IMS.RESLIB,DISP=SHR
//PFPSYSIN DD *

GLOBAL 
DBRC=YES
  END
  ANALYZE DBD=<dbdname>,IAREA=<areaname>,
    ACCESS=CONCURRENT
END
/*

DBRC considerations

DBRC must be active during execution of the concurrent analysis function. If the area is registered, a read-without-integrity authorization level for the area data set is requested. The data set name must match the name that is registered with DBRC.

MADS considerations (concurrent analysis process)

Multiple area data sets (MADS) are not supported by the concurrent analysis process.
The product searches the area data set (ADS) list that is registered for each area (in collating sequence by DD name). The product selects the first ADS that is marked as available for use and that has no error queue elements (EQEs). If an ADS is found that meets both of these criteria, it is the only ADS is analyzed. All other area data sets are ignored.