ch28.mht

如果想学习操作系统

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    <TD width=3D"100%"><PRE><IMG height=3D25 =
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gif" width=3D25><STRONG><FONT face=3D=CB=CE=CC=E5 color=3D#ff0000 =
size=3D3> </FONT><FONT face=3D=CB=CE=CC=E5 color=3D#e74914 =
size=3D5>=BD=F8</FONT><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D4>=B3=CC=B5=F7=B6=C8=CB=E3=B7=A8</FONT></STRONG><IMG height=3D21 =
src=3D"http://oa.gdut.edu.cn/os/multimedia/oscai/chapter2/images/arrow1.G=
IF" width=3D62></PRE></TD></TR></TBODY></TABLE>
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    <TD width=3D"100%"><PRE><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>    </FONT><IMG height=3D15 alt=3D"=C8=FD=BD=C7=BC=FD=CD=B7.GIF =
(188 bytes)" =
src=3D"http://oa.gdut.edu.cn/os/multimedia/oscai/chapter2/images/angle.GI=
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size=3D3><STRONG>=CF=C8=BD=F8=CF=C8=B3=F6=CB=E3=B7=A8</STRONG></FONT></PR=
E><PRE><FONT face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>        =
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src=3D"http://oa.gdut.edu.cn/os/multimedia/oscai/chapter2/images/gai.GIF"=
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color=3D#ff0080 size=3D3>=B4=A6=C0=ED=BB=FA</FONT><FONT =
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color=3D#000000 =
size=3D3>=A3=AC=B1=E3=D2=BB=D6=B1=D6=B4=D0=D0</FONT></PRE><PRE><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>    =
=CF=C2=C8=A5=A3=AC=D6=B1=B5=BD=B8=C3=BD=F8=B3=CC</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#ff0080 =
size=3D3>=CD=EA=B3=C9=BB=F2=D7=E8=C8=FB</FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 size=3D3>=CA=B1=A3=AC=B2=C5=CA=CD=B7=C5</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#ff0080 =
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color=3D#000000 size=3D3>=A1=A3</FONT></PRE><PRE><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>        </FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#008080 =
size=3D3><STRONG>=C0=FD=C8=E7</STRONG></FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 =
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=BD=F8=C8=EB</FONT><FONT face=3D=CB=CE=CC=E5 color=3D#ff0080 =
size=3D3>=BE=CD=D0=F7=B6=D3=C1=D0</FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 =
size=3D3>=A3=AC=CB=FC=C3=C7=B5=C4=D6=B4=D0=D0=C6=DA=B7=D6=B1=F0=CA=C721=A1=
=A26=BA=CD3=B8=F6=B5=A5=CE=BB=CA=B1=BC=E4=A3=AC</FONT></PRE><PRE><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>    =
=D6=B4=D0=D0=C7=E9=BF=F6=C8=E7=CF=C2=CD=BC=A3=BA</FONT></PRE>
      <DIV align=3Dcenter>
      <CENTER>
      <TABLE cellSpacing=3D0 cellPadding=3D0 width=3D"86%" border=3D0>
        <TBODY>
        <TR>
          <TD width=3D"4%">
            <P align=3Dcenter>0</P></TD>
          <TD width=3D"63%"></TD>
          <TD width=3D"3%">
            <P align=3Dcenter>21</P></TD>
          <TD width=3D"17%"></TD>
          <TD width=3D"3%">
            <P align=3Dcenter>27</P></TD>
          <TD width=3D"6%"></TD>
          <TD width=3D"4%">
            <P =
align=3Dcenter>30</P></TD></TR></TBODY></TABLE></CENTER></DIV>
      <DIV align=3Dcenter>
      <CENTER>
      <TABLE cellSpacing=3D1 width=3D"83%" border=3D1>
        <TBODY>
        <TR>
          <TD width=3D"69%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P1</FONT></STRONG></P></TD>
          <TD width=3D"21%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P2</FONT></STRONG></P></TD>
          <TD width=3D"10%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P3</FONT></STRONG></P></TD></TR>
        <TR>
          <TD width=3D"69%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>21</FONT></P></TD>
          <TD width=3D"21%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>6</FONT></P></TD>
          <TD width=3D"10%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000=20
        =
size=3D3>3</FONT></P></TD></TR></TBODY></TABLE></CENTER></DIV><PRE><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>        =
=B6=D4=D3=DAP1=A1=A2P2=A1=A2P3=B5=C4</FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#ff0080 size=3D3>=D6=DC=D7=AA=CA=B1=BC=E4</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>=CE=AA21=A1=A227=A1=A230=A3=AC</FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#ff0080 =
size=3D3>=C6=BD=BE=F9=D6=DC=D7=AA=CA=B1=BC=E4</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>=CE=AA26=A1=A3</FONT></PRE><PRE><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 size=3D3>        =
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</PRE><PRE><FONT face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>    =
</FONT><IMG height=3D15 alt=3D"=C8=FD=BD=C7=BC=FD=CD=B7.GIF (188 bytes)" =
src=3D"http://oa.gdut.edu.cn/os/multimedia/oscai/chapter2/images/angle.GI=
F" width=3D14><FONT face=3D=CB=CE=CC=E5 color=3D#800080 =
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=CB=E3=B7=A8(SCBF--Shortest CPU Burst =
First)</STRONG></FONT></PRE><PRE><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 size=3D3>        =B8=C3=CB=E3=B7=A8=B4=D3</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#ff0080 =
size=3D3>=BE=CD=D0=F7=B6=D3=C1=D0</FONT><FONT face=3D=CB=CE=CC=E5 =
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face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>        </FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#008080 =
size=3D3><STRONG>=C0=FD=C8=E7</STRONG></FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 size=3D3>=A3=AC=D4=DA</FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#ff0080 size=3D3>=BE=CD=D0=F7=B6=D3=C1=D0</FONT><FONT =
face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>=D6=D0=D3=D0=CB=C4=B8=F6=BD=F8=B3=CCP1=A1=A2P2=A1=A2P3=BA=CDP4=A3=
=AC=CB=FC=C3=C7=B5=C4=CF=C2=D2=BB=B8=F6=D6=B4=D0=D0=C6=DA=B7=D6=B1=F0=CA=C7=
16=A1=A212=A1=A24=BA=CD3</FONT></PRE><PRE><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000 size=3D3>    =
=B8=F6=B5=A5=CE=BB=CA=B1=BC=E4=A3=AC=D6=B4=D0=D0=C7=E9=BF=F6=C8=E7=CF=C2=CD=
=BC=A3=BA</FONT></PRE>
      <DIV align=3Dcenter>
      <CENTER>
      <TABLE cellSpacing=3D0 cellPadding=3D0 width=3D"86%" border=3D0>
        <TBODY>
        <TR>
          <TD width=3D"4%">
            <P align=3Dcenter>0</P></TD>
          <TD width=3D"5%"></TD>
          <TD width=3D"3%">
            <P align=3Dcenter>3</P></TD>
          <TD width=3D"8%"></TD>
          <TD width=3D"4%">
            <P align=3Dcenter>7</P></TD>
          <TD width=3D"29%"></TD>
          <TD width=3D"5%">
            <P align=3Dcenter>19</P></TD>
          <TD width=3D"38%"></TD>
          <TD width=3D"4%">
            <P =
align=3Dcenter>35</P></TD></TR></TBODY></TABLE></CENTER></DIV>
      <DIV align=3Dcenter>
      <CENTER>
      <TABLE cellSpacing=3D1 width=3D"83%" border=3D1>
        <TBODY>
        <TR>
          <TD width=3D"9%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P4</FONT></STRONG></P></TD>
          <TD width=3D"12%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P3</FONT></STRONG></P></TD>
          <TD width=3D"35%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P2</FONT></STRONG></P></TD>
          <TD width=3D"44%" bgColor=3D#fce3c2>
            <P align=3Dcenter><STRONG><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>P1</FONT></STRONG></P></TD></TR>
        <TR>
          <TD width=3D"9%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>3</FONT></P></TD>
          <TD width=3D"12%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>4</FONT></P></TD>
          <TD width=3D"35%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000 =
size=3D3>12</FONT></P></TD>
          <TD width=3D"44%">
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000=20
        =
size=3D3>16</FONT></P></TD></TR></TBODY></TABLE></CENTER></DIV><PRE><FONT=
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P1=A1=A2P2=A1=A2P3=BA=CDP4=B5=C4</FONT><FONT face=3D=CB=CE=CC=E5 =
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size=3D3>=CE=AA16=A1=A3</FONT></PRE><PRE><FONT face=3D=CB=CE=CC=E5 =
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FONT face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>    </FONT><IMG =
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face=3D=CB=CE=CC=E5 color=3D#000000 size=3D3>    =
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      <DIV align=3Dcenter>
      <CENTER>
      <TABLE cellSpacing=3D1 width=3D"83%" border=3D1>
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        <TR>
          <TD width=3D"18%" bgColor=3D#fce3c2>
            <P align=3Dcenter><FONT face=3D=CB=CE=CC=E5 color=3D#000000=20
            =
size=3D3><STRONG>=BE=B2=CC=AC=D3=C5=CF=C8=C8=A8</STRONG></FONT></P></TD>
          <TD width=3D"82%" bgColor=3D#aaf9a8><FONT face=3D=CB=CE=CC=E5 =
color=3D#000000=20
            size=3D3>&nbsp;&nbsp;&nbsp; </FONT><FONT face=3D=CB=CE=CC=E5 =
color=3D#ff0080=20
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