kernel.java

操作系统中内存管理页面置换算法的模拟程序

            }
            else
            {
              addr = Long.parseLong(tmp);
            }
            if (0 > addr || addr > address_limit)
            {
              System.out.println("MemoryManagement: " + addr + ", Address out of range in " + commands);
              System.exit(-1);
            }
            instructVector.addElement(new Instruction(command,addr));
          }
        }
      }
      in.close();
    } catch (IOException e) { /* Handle exceptions */ }
    runcycles = instructVector.size();
    if ( runcycles < 1 )
    {
      System.out.println("MemoryManagement: no instructions present for execution.");
      System.exit(-1);
    }
    if ( doFileLog )
    {
      File trace = new File(output);
      trace.delete();
    }
    runs = 0;
    for (i = 0; i < virtPageNum; i++) 
    {
      Page page = (Page) memVector.elementAt(i);
      if ( page.physical != -1 )
      {
        map_count++;
      }
      for (j = 0; j < virtPageNum; j++) 
      {
        Page tmp_page = (Page) memVector.elementAt(j);
        if (tmp_page.physical == page.physical && page.physical >= 0)
        {
          physical_count++;
        }
      }
      if (physical_count > 1)
      {
        System.out.println("MemoryManagement: Duplicate physical page's in " + config);
        System.exit(-1);
      }
      physical_count = 0;
    }
    if ( map_count < ( virtPageNum +1 ) / 2 )
    {
      for (i = 0; i < virtPageNum; i++) 
      {
        Page page = (Page) memVector.elementAt(i);
        if ( page.physical == -1 && map_count < ( virtPageNum + 1 ) / 2 )
        {
          page.physical = i;
          map_count++;
        }
      }
    }
    for (i = 0; i < virtPageNum; i++) 
    {
      Page page = (Page) memVector.elementAt(i);
      if (page.physical == -1) 
      {
        controlPanel.removePhysicalPage( i );
      } 
      else
      {
        controlPanel.addPhysicalPage( i , page.physical );
      }
    }
    for (i = 0; i < instructVector.size(); i++) 
    {
      high = block * virtPageNum;
      Instruction instruct = ( Instruction ) instructVector.elementAt( i );
      if ( instruct.addr < 0 || instruct.addr > high )
      {
        System.out.println("MemoryManagement: Instruction (" + instruct.inst + " " + instruct.addr + ") out of bounds.");
        System.exit(-1);
      }
    }
  } 

  public void setControlPanel(ControlPanel newControlPanel) 
  {
    controlPanel = newControlPanel ;
  }

  public void getPage(int pageNum) 
  {
    Page page = ( Page ) memVector.elementAt( pageNum );
    controlPanel.paintPage( page );
  }

  private void printLogFile(String message)
  {
    String line;
    String temp = "";

    File trace = new File(output);
    if (trace.exists()) 
    {
      try 
      {
        DataInputStream in = new DataInputStream( new FileInputStream( output ) );
        while ((line = in.readLine()) != null) {
          temp = temp + line + lineSeparator;
        }
        in.close();
      }
      catch ( IOException e ) 
      {
        /* Do nothing */
      }
    }
    try 
    {
      PrintStream out = new PrintStream( new FileOutputStream( output ) );
      out.print( temp );
      out.print( message );
      out.close();
    } 
    catch (IOException e) 
    {
      /* Do nothing */ 
    }
  }

  public void run()
  {
    step();
    while (runs != runcycles) 
    {
      try 
      {
        Thread.sleep(2000);
      } 
      catch(InterruptedException e) 
      {  
        /* Do nothing */ 
      }
      step();
    }  
  }

  public void step()
  {
    int i = 0;

    Instruction instruct = ( Instruction ) instructVector.elementAt( runs );
    controlPanel.instructionValueLabel.setText( instruct.inst );
    controlPanel.addressValueLabel.setText( Long.toString( instruct.addr , addressradix ) );
    getPage( Virtual2Physical.pageNum( instruct.addr , virtPageNum , block ) );
    if ( controlPanel.pageFaultValueLabel.getText() == "YES" ) 
    {
      controlPanel.pageFaultValueLabel.setText( "NO" );
    }
    if ( instruct.inst.startsWith( "READ" ) ) 
    {
      Page page = ( Page ) memVector.elementAt( Virtual2Physical.pageNum( instruct.addr , virtPageNum , block ) );
      if ( page.physical == -1 ) 
      {
        if ( doFileLog )
        {
          printLogFile( "READ " + Long.toString(instruct.addr , addressradix) + " ... page fault" );
        }
        if ( doStdoutLog )
        {
          System.out.println( "READ " + Long.toString(instruct.addr , addressradix) + " ... page fault" );
        }
        PageFault.replacePage( memVector , virtPageNum , Virtual2Physical.pageNum( instruct.addr , virtPageNum , block ) , controlPanel );
        controlPanel.pageFaultValueLabel.setText( "YES" );
      } 
      else 
      {
        page.R = 1;
        page.lastTouchTime = 0;   
        if ( doFileLog )
        {
          printLogFile( "READ " + Long.toString( instruct.addr , addressradix ) + " ... okay" );
        }
        if ( doStdoutLog )
        {
          System.out.println( "READ " + Long.toString( instruct.addr , addressradix ) + " ... okay" );
        }
      }
    }
    if ( instruct.inst.startsWith( "WRITE" ) ) 
    {
      Page page = ( Page ) memVector.elementAt( Virtual2Physical.pageNum( instruct.addr , virtPageNum , block ) );
      if ( page.physical == -1 ) 
      {
        if ( doFileLog )
        {
          printLogFile( "WRITE " + Long.toString(instruct.addr , addressradix) + " ... page fault" );
        }
        if ( doStdoutLog )
        {
           System.out.println( "WRITE " + Long.toString(instruct.addr , addressradix) + " ... page fault" );
        }
        PageFault.replacePage( memVector , virtPageNum , Virtual2Physical.pageNum( instruct.addr , virtPageNum , block ) , controlPanel );          controlPanel.pageFaultValueLabel.setText( "YES" );
      } 
      else 
      {
        page.M = 1;
        page.lastTouchTime = 0;
        if ( doFileLog )
        {
          printLogFile( "WRITE " + Long.toString(instruct.addr , addressradix) + " ... okay" );
        }
        if ( doStdoutLog )
        {
          System.out.println( "WRITE " + Long.toString(instruct.addr , addressradix) + " ... okay" );
        }
      }
    }
    for ( i = 0; i < virtPageNum; i++ ) 
    {
      Page page = ( Page ) memVector.elementAt( i );
      if ( page.R == 1 && page.lastTouchTime == 10 ) 
      {
        page.R = 0;
      }
      if ( page.physical != -1 ) 
      {
        page.inMemTime = page.inMemTime + 10;
        page.lastTouchTime = page.lastTouchTime + 10;
      }
    }
    runs++;
    controlPanel.timeValueLabel.setText( Integer.toString( runs*10 ) + " (ns)" );
  }

  public void reset() {
    memVector.removeAllElements();
    instructVector.removeAllElements();
    controlPanel.statusValueLabel.setText( "STOP" ) ;
    controlPanel.timeValueLabel.setText( "0" ) ;
    controlPanel.instructionValueLabel.setText( "NONE" ) ;
    controlPanel.addressValueLabel.setText( "NULL" ) ;
    controlPanel.pageFaultValueLabel.setText( "NO" ) ;
    controlPanel.virtualPageValueLabel.setText( "x" ) ;
    controlPanel.physicalPageValueLabel.setText( "0" ) ;
    controlPanel.RValueLabel.setText( "0" ) ;
    controlPanel.MValueLabel.setText( "0" ) ;
    controlPanel.inMemTimeValueLabel.setText( "0" ) ;
    controlPanel.lastTouchTimeValueLabel.setText( "0" ) ;
    controlPanel.lowValueLabel.setText( "0" ) ;
    controlPanel.highValueLabel.setText( "0" ) ;
    init( command_file , config_file );
  }
}