![]() |
![]() |
The GLMSELECT Procedure |
PERFORMANCE Statement |
The PERFORMANCE statement is used to change default options that affect the performance of PROC GLMSELECT and to request tables that show the performance options in effect and timing details.
The following options are available:
specifies the number of processors that PROC GLMSELECT assumes are available for multithreaded BY-group processing. CPUCOUNT=ACTUAL sets CPUCOUNT to be the number of physical processors available. Note that this can be less than the physical number of CPUs if the SAS process has been restricted by system administration tools. Setting CPUCOUNT= to a number greater than the actual number of available CPUs might result in reduced performance. This option overrides the SAS system option CPUCOUNT=. If CPUCOUNT=1, then NOTHREADS is in effect, or if no BY processing is being used, then PROC GLMSELECT uses singly threaded code.
requests the "PerfSettings" table that shows the performance settings in effect and the "Timing" table that provides a broad timing breakdown of the PROC GLMSELECT step.
specifies whether the SSCP matrix is built incrementally as the selection process progresses or whether the SCCP matrix for the full model is built at the outset. Building the SSCP matrix incrementally can significantly reduce the memory required and the time taken to perform model selection in cases where the number of parameters in the selected model is much smaller than the number of parameters in the full model, but it can hurt performance in other cases since it requires at least one pass through the model training data at each step. If you use backward selection or no selection, or if the BIC or CP statistics are required in the selection process, then the BUILDSSCP=INCREMENTAL option is ignored. In other cases, BUILDSSCP=INCREMENTAL is used by default if the number of effects is greater than 100. See the section Building the SSCP Matrix for further details.
enables multithreaded BY-group computation. This option overrides the SAS system option THREADS | NOTHREADS. If no BY processing is being used, then PROC GLMSELECT ignores this option and uses singly threaded code.
disables multithreaded BY-group computation. This option overrides the SAS system option THREADS | NOTHREADS.
![]() |
![]() |
Copyright © 2009 by SAS Institute Inc., Cary, NC, USA. All rights reserved.