$size = $chunk_size =~ /(\d+)g/i ? $1 * 1024*1024*1024 :
        $chunk_size =~ /(\d+)m/i ? $1 * 1024*1024 :
        $chunk_size =~ /(\d+)k/i ? $1 * 1024 :          # easy addition
        $chunk_size;