| Parameter | Specify . . . | Possible Values | Default |
|---|---|---|---|
| PREFXCMD | the commands to exclude from prefetch processing. | L1-L9 | none |
| PREFXFIL | the files to exclude from prefetch processing. | 1-5000 | none |
Together, PREFXFIL and PREFXCMD specify one or more files to be excluded from prefetch/multifetch processing. PREFXFIL specifies one or more files by file number; PREFXCMD specifies a command for each file number.
You can either "include" list of files using PREFIFIL/PREFICMD ) or "exclude" lists of files using the parameters PREFXFIL/PREFXCMD, depending on which list is shorter. You cannot both include and exclude files at the same time.
If prefetching/multifetching has been specified and
files/commands have been neither included nor excluded, the prefetching/multifetching applies to all files by default.
files/commands have been exncluded using PREFXFIL/PREFXCMD, the prefetching/ multifetching applies only to the files on the "exclusion" list.
both PREFIFIL/PREFICMD and PREFXFIL/PREFXCMD are specified, Adabas recognizes the exclusion parameters PREFXFIL/PREFXCMD and ignores the inclusion parameters PREFIFIL/PREFICMD.
Exclude the L3 command for file 8 from prefetch processing.
ADARUN PREFXFIL=8,PREFXCMD=L3
Specify multiple file numbers in multiple PREFXFIL statements or in a list, separated by commas. Specify multiple commands in multiple PREFXCMD statements or in a list, separated by slashes (/). The maximum number of entries for each is 50.
If you use lists, they must have the same number of entries. There is a one-to-one correspondence, by position, between a file number in the PREFXFIL list and a command in the PREFXCMD list.
Exclude the L3 command for file 8 and the L3 and L9 commands for file 12 from prefetch/multifetch processing.
ADARUN PREFXFIL=8,12,12,PREFXCMD=L3/L3/L9
or
ADARUN PREFXFIL=8,PREFXCMD=L3 ADARUN PREFXFIL=12,PREFXCMD=L3 ADARUN PREFXFIL=12,PREFXCMD=L9
As the preceding example shows, you can specify the same file number several times, with a different command each time. Likewise, you can specify the same command code several times, with a different file number each time.
The following commands can be excluded from prefetch/multifetch processing for a file:
L1/L4
L2/L5
L3/L6
L9
If either command in one of the pairs above is specified in a PREFXCMD statement, both commands are excluded. For example, if PREFXCMD=L1 is specified, both L1 and L4 are excluded.
Execute a user program with multifetch and allocate 20,000 bytes for the total prefetch buffer area. Exclude the L3 and L6 commands for files 8 and 12 from multifetch processing. Exclude all commands for file 7.
ADARUN PROG=USER,PREFETCH=YES,PREFTBL=20000 ADARUN PREFXFIL=8,12,PREFXCMD=L3/L3 ADARUN PREFXFIL=7,7,7,7,PREFXCMD=L1/L2/L3/L9
No PREFSBL value is specified, so the buffer length for a single prefetch sequence defaults to 3,000 bytes; up to 6 prefetch sequences can be handled.
