presto-main/src/main/java/io/prestosql/sql/planner/planprinter/TextRenderer.java/TextRenderer/printWindowOperatorStats
class TextRenderer:    private void printWindowOperatorStats(StringBuilder output, WindowOperatorStats stats)
    {
        if (!verbose) {
            // these stats are too detailed for non-verbose mode
            return;
        }

        output.append(format("Active Drivers: [ %d / %d ]\n", stats.getActiveDrivers(), stats.getTotalDrivers()));
        output.append(format("Index size: std.dev.: %s bytes, %s rows\n", formatDouble(stats.getIndexSizeStdDev()), formatDouble(stats.getIndexPositionsStdDev())));
        output.append(format("Index count per driver: std.dev.: %s\n", formatDouble(stats.getIndexCountPerDriverStdDev())));
        output.append(format("Rows per driver: std.dev.: %s\n", formatDouble(stats.getRowsPerDriverStdDev())));
        output.append(format("Size of partition: std.dev.: %s\n", formatDouble(stats.getPartitionRowsStdDev())));
    }