VSAM Performance Enhancement › VPE Operation › VPE Rules Table › Data Set Specific Parameters

Data Set Specific Parameters

These parameters are valid only when the RULE statement specifies DDNAME= or DSNAME=:

POWERFACT=nn

Directs VPE to obtain additional buffers for the data set(s) specified on the RULE statement. This parameter provides a means of distributing the available buffer space on a file-by-file basis. POWERFACT= does not affect the size of the buffer pool (see TGTBUF=). The default value is 1.

SIS=NO|YES

SIS= directs VPE to activate VSAM's Sequential Insert Strategy for the data set(s) specified on the RULE statement. The default value is SIS=NO.

DFW=NO|YES

DFW= directs VPE to activate Deferred Write for the data set(s) specified on the RULE statement. The default is DFW=NO.

Note: Setting SIS=YES and DFW=YES is equivalent to the CICSWRK control DD.

FORCEMODE=SEQ|LSR

FORCEMODE= directs VPE to force either sequential performance enhancements or LSR optimization, if possible, for the data set(s) specified on the RULE statement. There is no default for this parameter. When FORCEMODE= is omitted, VPE uses an algorithm to automatically select one type of optimization or the other.

BUFND=nn

BUFND= specifies the number of buffers VPE is to acquire for the VSAM data component. This parameter overrides VPE's automatic computations.

BUFNI=nn

BUFNI= specifies the number of buffers VPE is to acquire for the VSAM index component. This parameter overrides VPE's automatic computations.

BUFSP=nn

BUFSP= specifies the size of the VSAM buffer space. This parameter overrides VPE's automatic computations.

VSAMREC=NO|YES

VSAMREC= directs VPE to produce the VSAM Recommendations Report.