The number of buffers
is not a permanent attribute of the data set; it is valid only for
the current SAS session or job.
BUFNO= applies to SAS
data sets that are opened for input, output, or update.
Using BUFNO= can improve
execution time by limiting the number of input/output operations that
are required for a particular SAS data set. The improvement in execution
time, however, comes at the expense of increased memory consumption.
Under Windows, the maximum
number of buffers that you can allocate is determined by the amount
of memory available. To request that SAS allocate the number of buffers
based on the number of pages for the data set, use the SASFILE statement.