private String toCSV() {
            return String.format("%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d", _indexPageCount, _indexBytesInUse,
                    _dataPageCount, _dataBytesInUse, _longRecordPageCount, _longRecordBytesInUse, _mvvPageCount,
                    _mvvCount, _mvvOverhead, _mvvAntiValues, _indexHoleCount, _prunedPageCount);
        }