DSNJLOGF (preformat active log)

When writing to an active log data set for the first time, Db2 must preformat a VSAM control area before writing the log records. The DSNJLOGF stand-alone utility avoids this delay by preformatting the active log data sets before bringing them online to Db2.

The following EXEC statement is used to invoke DSNJLOGF:

//stepname EXEC PGM=DSNJLOGF

Environment

Run DSNJLOGF as a z/OS® job.

Required and optional data sets

All SYSUTx DD statements are optional, but at least one must be specified.

DSNJLOGF recognizes DD statements with the following DD names.

SYSUT0: Defines the newly defined active log data set that is to be preformatted. The data set must be an empty VSAM linear data set.
SYSUT1: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT2: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT3: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT4: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT5: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT6: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT7: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT8: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSUT9: Defines a newly defined active log data set that is to be preformatted. This statement is optional.
SYSPRINT: Defines the print spool class or data set for print output. The logical record length (LRECL) is 132.

Sample DSNJLOGF control statement

The control statements in the following example specify that DSNJLOGF is to preformat the active log data sets that are identified by the DD statements.

//MULTFMT  EXEC PGM=DSNJLOGF,REGION=64M 
//SYSPRINT  DD SYSOUT=* 
//SYSUT0    DD DSN=DSNTEMP.LOGCOPY1.DS00,DISP=SHR
//SYSUT1    DD DSN=DSNTEMP.LOGCOPY1.DS01,DISP=SHR
//SYSUT2    DD DSN=DSNTEMP.LOGCOPY1.DS02,DISP=SHR
//SYSUT3    DD DSN=DSNTEMP.LOGCOPY1.DS03,DISP=SHR
//SYSUT4    DD DSN=DSNTEMP.LOGCOPY1.DS04,DISP=SHR
//SYSUT5    DD DSN=DSNTEMP.LOGCOPY1.DS05,DISP=SHR
//SYSUT6    DD DSN=DSNTEMP.LOGCOPY1.DS06,DISP=SHR
//SYSUT7    DD DSN=DSNTEMP.LOGCOPY1.DS07,DISP=SHR
//SYSUT8    DD DSN=DSNTEMP.LOGCOPY1.DS08,DISP=SHR
//SYSUT9    DD DSN=DSNTEMP.LOGCOPY1.DS09,DISP=SHR

DSNJLOGF output

The following sample shows the DSNJLOGF output for the second data set in the previous sample control statement shown above.

DSNJ991I DSNJLOGF START OF LOG DATASET PREFORMAT FOR JOB LOGFRMT  STEP1
DSNJ992I DSNJLOGF LOG DATA SET NAME = DSNC112.LOGCOPY1.DS01
DSNJ996I DSNJLOGF LOG PREFORMAT COMPLETED SUCCESSFULLY, 00015000
         RECORDS FORMATTED