DataTable和普通类型存储数据,内存和效率的差别

测试了一下普通的dt和类型的速度差异, 下面是代码:

代码

public class MrInfo
{
public int versionid { get; set; }
public string MCellId { get; set; }
public int NCell_Bcch { get; set; }
public int NCell_Bsic { get; set; }
public double RMS0 { get; set; }
public double RMS1 { get; set; }
public double RMS2 { get; set; }
public double RMS3 { get; set; }
public double RMS4 { get; set; }
public double RMS5 { get; set; }
public double RMS6 { get; set; }
public double RMS7 { get; set; }
public double RMS8 { get; set; }
public double RMS9 { get; set; }
public double Total { get; set; }
public DateTime CollectTime { get; set; }
}

class Program
{
static void Main(string[] args)
{
Console.WriteLine(DateTime.Now);
//TestNullableInt();
//List<MrInfo> lstMr = TastClass();
//DataTable dt = TestDataTable();
Console.WriteLine();
Console.WriteLine(DateTime.Now);
Console.WriteLine("==OVER==");
Console.ReadLine();
}

private static void TestNullableInt()
{
int i = 100;
int j = 50;
Console.WriteLine("i:{0},j:{1}", i, j);
TestInt(i, ref j);
Console.WriteLine("TestInt(int i, ref int j) i:{0},j:{1}", i, j);
int? ni = 100;
int? nj = 50;
Console.WriteLine("ni:{0},nj:{1}", ni.Value, nj.Value);
TestNullInt(ni, ref nj);
Console.WriteLine("TestNullInt(int? i, ref int? j) i:{0},j:{1}", ni.Value, nj.Value);
}

static void TestInt(int i, ref int j)
{
i++;
j++;
}

static void TestNullInt(int? i, ref int? j)
{
i = i.Value + 1;
j = j.Value + 1;
}

static List<MrInfo> TastClass()
{
List<MrInfo> lstInfo = new List<MrInfo>();
for (int i = 0; i <= 4000000; i++)
{
MrInfo mr = new MrInfo()
{
CollectTime = DateTime.Now,
MCellId = "460-00-11111-" + i.ToString("00000"),
NCell_Bcch = 6,
NCell_Bsic = 7,
RMS0 = 0,
RMS1 = 1,
RMS2 = 2,
RMS3 = 3,
RMS4 = 4,
RMS5 = 5,
RMS6 = 6,
RMS7 = 7,
RMS8 = 8,
RMS9 = 9,
Total = 10,
versionid = 1
};
lstInfo.Add(mr);
if (i % 100000 == 0)
Console.Write("^");
}
return lstInfo;
}

static DataTable TestDataTable()
{
DataTable dt = GetMRTableSchema();
for (int i = 0; i <= 3000000; i++)
{
DataRow dr = dt.NewRow();
dr[0] = 1;
dr[1] = "460-00-11111-" + i.ToString("00000");
dr[2] = 6;
dr[3] = 7;
for (int j = 0; j < 11; j++)
{
dr[4 + j] = j;
}
dr["CollectTime"] = DateTime.Now;
dt.Rows.Add(dr);
if (i % 100000 == 0)
Console.Write("^");
}
return dt;
}

static DataTable GetMRTableSchema()
{
DataTable mrDataTable = new DataTable();
mrDataTable.Columns.Add("versionid", typeof(Int32));
mrDataTable.Columns.Add("MCellId", typeof(String));
mrDataTable.Columns.Add("NCell_Bcch", typeof(Int32));
mrDataTable.Columns.Add("NCell_Bsic", typeof(Int32));
mrDataTable.Columns.Add("RMS0", typeof(double));
mrDataTable.Columns.Add("RMS1", typeof(double));
mrDataTable.Columns.Add("RMS2", typeof(double));
mrDataTable.Columns.Add("RMS3", typeof(double));
mrDataTable.Columns.Add("RMS4", typeof(double));
mrDataTable.Columns.Add("RMS5", typeof(double));
mrDataTable.Columns.Add("RMS6", typeof(double));
mrDataTable.Columns.Add("RMS7", typeof(double));
mrDataTable.Columns.Add("RMS8", typeof(double));
mrDataTable.Columns.Add("RMS9", typeof(double));
mrDataTable.Columns.Add("Total", typeof(double));
mrDataTable.Columns.Add("CollectTime", Type.GetType("System.DateTime"));
return mrDataTable;
}
}

及时结果差异巨大:
第一列是内存(M)第二列是执行时间(S)

DT

1百万

330	13
333	12
366	12
366	11
368	12

2百万

604	26
600	25
670	26
688	26

3百万

1200	37
1200	37
1200	37

4百万

1200	41
1200	50

Class

1百万

205	3
206	3
205	3
205	3
205	3

2百万

387	6
388	6
388	7
389	6
389	6

3百万

568	10
570	9
570	9
570	9
571	10

4百万

742	12
744	11
743	12