Net7/JDK19/Delphi10性能对比(续)
很多老哥说不公平、索要代码,亦有delphi大佬直接不相信。性能强弱是多方面的,我这里只测试内存分配及运算速度,C#圈的大佬各种不相信也是正常,毕竟可能C#其他方面吊打java,大家可以show code.
测试用的这个所谓的阵列运算其实来自Python的一个函数,当时认为python怎么调用一个函数要花费这么长的时间(都说python底层是用c/c++写的),好奇之下用c#,java,c++,c#都实现了一遍,当年测试的结果如下:
至于有c#圈的老哥说,java没算gc的耗时,我觉得挺搞笑的,c#的语法和运行方式几乎和java一样,如果你能举个类似的例子能证明c#吊打java,请提供代码。
先上delphi的代码,当时因为要兼容codetypon好像已经“优化”过了,用的指针操作:
type
TarrInt = array of pinteger;
procedure TForm1.Button1Click(Sender: TObject);
var
lvStart, lvEnd: cardinal;
lvArr: TarrInt;
lvSize: integer;
col, row: integer;
lvSum: UInt64;
lvVal: pinteger;
lvOut: pchar;
begin
lvSize := 10000;
{ getmem(lvOut,1);
fillchar(lvOut^,0,1); }
lvOut := strnew('');
lvStart := GetTickCount;
setLength(lvArr, lvSize);
for row := 0 to lvSize - 1 do
begin
getmem(lvArr[row], sizeof(integer) * lvSize);
lvVal := lvArr[row];
for col := 0 to lvSize - 1 do
begin
// lvVal:=integer(lvVal)+1;
lvVal^ := col + 1;
Inc(lvVal);
end;
end;
lvEnd := GetTickCount();
// lvOut.add(Format('Create lvArray Use:%d', [lvEnd - lvStart]));
StrCat(lvOut, pchar(Format('阵列创建耗时:%d'#13#10,
[lvEnd - lvStart])));
lvStart := GetTickCount;
lvSum := 0;
for row := 0 to lvSize - 1 do
begin
lvVal := lvArr[row];
for col := 0 to lvSize - 1 do
begin
lvSum := lvSum + lvVal^;
Inc(lvVal);
end;
end;
for row := 0 to lvSize - 1 do
begin
freemem(lvArr[row]);
end;
lvEnd := GetTickCount();
StrCat(lvOut, pchar(Format('运算结果 :%d'#13#10, [lvSum])));
StrCat(lvOut, pchar(Format('计算耗时:%d'#13#10,
[lvEnd - lvStart])));
Memo1.Text := strpas(lvOut);
StrDispose(lvOut);
// memo1.Lines.Text := lvOut.Text;
end;
JAVA:
long start = System.currentTimeMillis();
int[][] array = new int[10000][10000];
for (int row = 0; row < array.length; row++) {
for (int col = 0; col < array[row].length; col++) {
array[row][col] = col + 1;
}
}
long end = System.currentTimeMillis();
System.out.println(String.format("阵列创建耗时:%d", end - start));
start = System.currentTimeMillis();
long total = 0;
for (int row = 0; row < array.length; row++) {
for (int col = 0; col < array[row].length; col++) {
total += array[row][col];
}
}
end = System.currentTimeMillis();
System.out.println(String.format("运算结果:%d", total));
System.out.println(String.format("运算耗时:%d", end-start));
C#:
const int arrLength = 10000;
long start = Environment.TickCount;
int[][] arr = new int[arrLength][];
for (int row = 0; row < arrLength; row++)
{
arr[row] = new int[arrLength];
for (int col = 0; col < arrLength; col++)
{
arr[row][col] = col + 1;
}
}
long end = Environment.TickCount;
Console.WriteLine(String.Format("阵列创建耗时:{0}", end - start));
start = Environment.TickCount;
long total = 0;
for (int row = 0; row < arrLength; row++)
{
for (int col = 0; col < arrLength; col++)
{
total += arr[row][col];
}
}
end = Environment.TickCount;
Console.WriteLine(String.Format("运算结果:{0}", total));
Console.WriteLine(String.Format("运算耗时:{0}", end - start));
java和C#代码几乎一样,java用maven生成jar后,在控制台跑10次,取平均值, c#用release net7框架编译后,在控制台跑10次,取平均值,都是默认参数,没有进行所谓的优化微调。
net7,java(jdk19)的最新对比结果:
https://www.toutiao.com/w/1750086031059972