csdn_文档中心_关注内存 提高软件性能(3).htm

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                  style="COLOR: #000066; FONT-SIZE: 16pt; mso-bidi-font-size: 24.0pt; mso-bidi-font-family: 宋体; mso-ansi-language: ZH-CN"><o:p>&nbsp;</o:p></SPAN></P></DIV></TD></TR></TBODY></TABLE></v:textbox></v:shape><v:line 
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            endarrow="block" dashstyle="dash"></v:stroke><v:shadow 
            color="black"></v:shadow></v:line><?xml:namespace prefix = w ns = 
            "urn:schemas-microsoft-com:office:word" /><w:wrap 
            type="none"></w:wrap><w:anchorlock></w:anchorlock></v:group></SPAN><SPAN 
            lang=EN-US><o:p></o:p></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">要看明白</SPAN><SPAN 
            lang=EN-US>slab</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">算法的代码还是要费点时间的用到自己的程序里面到是很简单</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">只要加那</SPAN><SPAN 
            lang=EN-US>2</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">个宏就可以了</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">如果不想下载</SPAN><SPAN 
            lang=EN-US>myicq</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的代码而想用的话</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">可以到这里看看</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT 
            size=3>http://yj000885.sosoo.net/3Ddoc/testslab.htm<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><o:p><FONT size=3>&nbsp;</FONT></o:p></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">需要说明的是</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">一般情况下是不需要自己定义内存的管理方式的</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">一般比较大的项目</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">对性能要求比较高</SPAN><SPAN 
            lang=EN-US>(</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">比如游戏</SPAN><SPAN 
            lang=EN-US>engine)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">需要用到</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">一般用系统自己定义的方式就可以了</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">还有一种是</SPAN><SPAN 
            lang=EN-US>&lt;&lt;windows</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">高级编程</SPAN><SPAN 
            lang=EN-US>&gt;&gt;</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">里面介绍的</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">我想也可以一定程度上提高性能</SPAN><SPAN 
            lang=EN-US>.</SPAN></FONT></P>
            <P class=MsoNormal 
            style="MARGIN: 0cm 0cm 0pt 18pt; TEXT-INDENT: -18pt; mso-list: l0 level1 lfo1; tab-stops: list 18.0pt"><SPAN 
            lang=EN-US style="mso-fareast-font-family: 'Times New Roman'"><SPAN 
            style="mso-list: Ignore"><FONT size=3>1.</FONT><SPAN 
            style="FONT: 7pt 'Times New Roman'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN></SPAN></SPAN><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">这种是与平台相关的方法了</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">适用于</SPAN><SPAN 
            lang=EN-US>win32</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">平台下</SPAN><SPAN 
            lang=EN-US>.</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">我们知道</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">当调用</SPAN><SPAN 
            lang=EN-US>new</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的时候</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">对象是分配在堆上</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">如果每个对象的实例都有一个堆</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">那么当创建一个对象</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">销毁一个对象</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">再创建对象的时候就需要再次分配一个堆</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">然后再销毁</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">开销就比较大</SPAN><SPAN 
            lang=EN-US>.</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">可以用下面的思路来减少开销</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">为每个类创建一个堆</SPAN><SPAN 
            lang=EN-US>,</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">该类的每个实例都分配在该堆上</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">这样可以减少开销</SPAN><SPAN 
            lang=EN-US>.</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">看下面的代码</SPAN><SPAN 
            lang=EN-US>:</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>Class Testclass</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>{</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>private:</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>static HHEAP s_heap;</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>static UINT 
            s_uNumAllosInHeap;</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>public:</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US>//</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">重载</SPAN><SPAN 
            lang=EN-US>operator new ,delete</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>void* operator new(size_t 
            size)</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3>{</FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT siz