📄 ch7.htm
字号:
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">提高</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">CPU</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">和</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">I/O</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">设备之间的并行性。</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l12 level1 lfo21"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">2．</span><span style="mso-ascii-font-family: Times New Roman">单缓冲</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l12 level1 lfo21"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">3．</span><span style="mso-ascii-font-family: Times New Roman">双缓冲</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l12 level1 lfo21"><font color="#FFFFFF"><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">4．<span style="font-style: normal; font-variant: normal; font-weight: normal">
</span></span><span style="mso-ascii-font-family: Times New Roman">循环缓冲</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑴组成——多个缓冲区、多个指针</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑵缓冲区的使用——</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Getbuf</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">过程、</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Releasebuf</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">过程</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑶进程同步——</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Nexti</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">指针追上</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Nextg</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">指针、</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Nextg</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">指针追上</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Nexti</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">指针</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l12 level1 lfo21"><font color="#FFFFFF"><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">5．<span style="font-style: normal; font-variant: normal; font-weight: normal">
</span></span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">缓冲池</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑴缓冲池的组成——空缓冲队列</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">emq</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">、输入队列</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">inq</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">、输出队列</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">outq<o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑵</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Getbuf</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">过程和</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">Putbuf</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">过程</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑶缓冲区的工作方式——收容输入工作方式、提取输出工作方式、收容输出工作方式、提取输出工作方式</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
</td>
</tr>
<tr>
<td width="114%" align="left" height="51" colspan="2">
<p style="TEXT-ALIGN: center" align="center"><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><font color="#FFFFFF"><a name="ch74"></a>7．4设备分配<o:p>
</o:p>
</font></span></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l28 level1 lfo22"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">1．</span><span style="mso-ascii-font-family: Times New Roman">设备分配中的数据结构</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">逻辑设备表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">LUT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）→系统设备表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">SDT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）→设备控制表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">DCT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）→控制器控制表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">COCT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）→通道控制表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">CHCT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l28 level1 lfo22"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">2．</span><span style="mso-ascii-font-family: Times New Roman">设备分配时应考虑的若干因素</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑴考虑设备的固有属性</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">独享设备、共享设备、虚拟设备</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑵设备分配算法：</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">先来先服务、优先级高者优先</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑶设备分配的安全性</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">安全分配方式</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">不安全分配方式</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l28 level1 lfo22"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">3．</span><span style="mso-ascii-font-family: Times New Roman">设备独立性</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑴设备独立性</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">设备独立性概念：应用程序独立于具体使用的物理设备</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">设备独立性优点：设备分配时的灵活性；易于实现</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">I/O</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">重定向</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US"> </span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑵设备独立性软件</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">完成功能：执行所有设备的公有操作；向用户层（或文件层）软件提供统一的接口</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US"> </span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑶逻辑设备名到物理设备名映射的实现</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt"><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">逻辑设备表（</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">LUT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">）；</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">LUT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">的设置问题——整个系统设置一张</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">LUT</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">、每个用户设置一张</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt">LUT<o:p>
</o:p>
</span></font></p>
<p style="MARGIN-LEFT: 18pt; TEXT-INDENT: -18pt; tab-stops: list 18.0pt; mso-list: l28 level1 lfo22"><font color="#FFFFFF"><span lang="EN-US" style="mso-fareast-font-family: 黑体">4．</span><span style="mso-ascii-font-family: Times New Roman">独占设备的分配程序</span><span lang="EN-US" style="mso-fareast-font-family: 黑体"><o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">⑴基本的设备分配程序</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">分配设备</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
<p><font color="#FFFFFF"><span style="mso-spacerun: yes; mso-bidi-font-size: 10.0pt" lang="EN-US">
</span><span style="mso-bidi-font-size: 10.0pt; mso-ascii-font-family: Times New Roman; mso-hansi-font-family: Times New Roman">分配控制器</span><span lang="EN-US" style="mso-bidi-font-size: 10.0pt"><o:p>
</o:p>
</span></font></p>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -