Why do some plots execute more quickly than others?

    Some PLOT commands execute more quickly than others because PCA
    uses all available information from the previous plot to produce
    the requested one. For example, if you enter PLOT PROGRAM BY
    LINE, and then enter PLOT/DESCENDING, PCA will only sort the
    previous plot. However, if you use a different nodespec, such
    as PLOT ROUTINE foo$bar BY CODEPATH, then PCA must rebuild its
    internal tables and read the data again, which takes more time.
    In addition, the number of filters and/or buckets you use affects
    the time it takes to build a plot. This is because filters affect
    the amount of data the Analyzer looks at, and because all buckets
    must be searched for each data point.