When you specify SORTPGM=BEST,
SAS uses the value of the SORTCUT and SORTCUTP options to determine
whether to use the host sort or the SAS sort. If the data set to
be sorted is larger than the number of bytes (or kilobytes or megabytes)
that you specify with SORTCUTP, the host sort will be used instead
of the SAS sort. The value that you specify must be less than or equal
to 2,147,483,647 bytes. If both SORTCUT and SORTCUTP are either not
defined or are set to 0, the SAS sort is used. If you specify both
options and either condition is true, SAS chooses the host sort.
The following equation
computes the number of bytes to be sorted:
number-of-bytes= ((length-of-obs)+(length-of-all-keys))*number-of-obs