Chapter 2 TECHNICAL REFERENCE ON IMPROVING THE OPERATION OF WINDOWS (Also contained in the disk file "W2IMPROV.TXT".) CONTENTS OF CHAPTER 2 1. CHAPTER INTRODUCTION 15 2. MODIFYING CONFIG.SYS 15 2.1 Buffers and Files 15 2.2 Environment Space 16 3. MODIFYING AUTOEXEC.BAT 16 3.1 SMARTDrive Disk Cache 16 3.2 Double Buffering 18 3.3 The TEMP Environment Variable 18 3.4 Removing Non-Functioning TSRs 19 4. REMOVING UNNECESSARY HARD DISK FILES 19 4.1 Files in the \WINDOWS Subdirectory 19 4.2 Old Windows Swap Files 21 1. CHAPTER INTRODUCTION This chapter provides a few tips about improving the performance of Windows. Tips are based on our experience with running Windows version 3.1 with MSDOS 6.2 on a 486 DX-66 PC with more than 20 MB of free hard disk space and 8 MB of PC memory. You must determine for yourself whether the suggestions presented in this chapter are relevant to your situation. These suggestions may not be appropriate for all PC's. Please refer to your Windows documentation from Microsoft when you have questions regarding the applicability of suggestions or need greater detail. 2. MODIFYING CONFIG.SYS The following suggestions require you to modify your CONFIG.SYS file. It is best to make a backup copy of this file before you modify it. A text editor should be used to make changes in your CONFIG.SYS file. If you use a word processing program to modify this file, then be sure to save the file as a DOS text file or in a non-document format after completing your changes. The file will not function properly when it is saved as a word processing file. 2.1 Buffers and Files As a general rule, you should set BUFFERS equal to 20 or less. Since we recommend that you use Windows SMARTDrive, then you can set BUFFERS equal to 10. The use of SMARTDrive is discussed later in this chapter. If you plan to run non-Windows applications in DOS windows, then it is necessary to have an adequate number of file handles. The number of FILES should be set to a number between 30 and 50. 2.2 Environment Space The SHELL command indicates the command interpreter that is used when you switch to the MS-DOS prompt. It also specifies environment space. Your SHELL command should be similar to the following example. SHELL=C:\DOS\COMMAND.COM /P /E:1024 The number at the end of this command specifies the Environment Space. Your environment space normally should not be smaller than 1024 bytes when running Windows. 3. MODIFYING AUTOEXEC.BAT When making changes to AUTOEXEC.BAT, you need to use a text editor. It is best to make a backup copy of this file before you make changes in it. If you use a word processing program to modify this file, then be sure to save the file as a DOS text file or in a non-document format when you have completed your changes. This insures that the file will function properly. 3.1 SMARTDrive Disk Cache Adding the SMARTDrive Disk Cache program to your AUTOEXEC.BAT file can speed up the operation of Windows. The SMARTDrive program copies information from your hard disk and keeps it in extended memory so that it can be rapidly accessed when it is needed. It also can temporarily store information before it is written to your hard disk. The cache allows certain tasks to be completed without the necessity of waiting for the hard disk to respond. The sample command line that is shown below creates a default disk cache. C:\DOS\SMARTDRV.EXE The Windows installation program normally installs SMARTDrive in your AUTOEXEC.BAT file. If your AUTOEXEC.BAT file does not contain this command, then you should add it. Please note! Do not use SMARTDrive unless you have more than 2 MB of memory. The proper use of the SMARTDrive command depends on many variables, and there is no single best setup for SMARTDrive. We will discuss two variables that you can test in order to improve your system's performance. Additional information about SMARTDrive is available in the Windows documentation that was supplied by Microsoft, and in the MSDOS help system. To use MSDOS Help to obtain information about SMARTDrive: Type HELP SMARTDRIVE at a DOS prompt and press ENTER. To increase the performance of SMARTDrive you should specify the size of the cache. A sample SMARTDrive command that specifies an initial cache size and a Windows cache size is shown below. C:\DOS\SMARTDRV.EXE 2048 1024 The value "2048" is the size of the cache that is used before Windows is loaded. The value "1024" is the minimum size of the cache that is used when Windows is running. The number of bytes used for these values is directly related to the system memory on your PC. The following chart suggests values for PC's with various amounts of system memory. Please remember, these are only suggestions, and experimentation is probably needed. If your PC has 4 MB of extended memory, then try these cache sizes. Initial Cache Size = 1024 Windows Cache Size = 512 If your PC has 8 MB or more of extended memory, then try these cache sizes. Initial Cache Size = 2048 Windows Cache Size = 2048 (Even though 8 MB of memory was used on our PC, we found that we had better performance when the Windows cache size was set to 1024.) Please note! To be sure that SMARTDrive has written all data to the hard disk before you turn off your PC, type the following command at a DOS prompt. Type SMARTDRV /C press ENTER. 3.2 Double Buffering If you have a small computer system interface hard disk (SCSI), then you may need to use the Double-buffering feature of SMARTDrive. Double buffering provides compatibility for hard disk controllers that cannot work with virtual memory. Please refer to your Microsoft documentation for information about using SMARTDrive's double buffering feature. Double buffering is usually only required with older hard disks. 3.3 The TEMP Environment Variable Windows uses Temporary Swap Files to store data. Be sure that you have a SET Command in your AUTOEXEC.BAT that tells Windows where to store these files. A sample SET command is shown below. Also, be sure that the subdirectory, to which it points, actually exists on your hard disk. SET TEMP=C:\WINDOWS\TEMP 3.4 Removing Non-Functioning TSRs The AUTOEXEC.BAT file may be used to load various Terminate and Stay Resident (TSR) programs. Most of these DOS based programs cannot be used in Windows, and they occupy valuable space in conventional memory. You should remove all TSRs that cannot be used in Windows. You can create a batch file that can load your DOS TSRs at those times when you plan to work in the DOS environment. If you routinely use the DOS version of JAWS and it is loaded by your AUTOEXEC.BAT, then you can manually remove JAWS from memory with the ALT+SHIFT+F1 before loading Windows. You should not have the DOS Version of JAWS in memory when you load Windows, unless you plan to use the DOS version of JAWS in a DOS application window. Information about running the DOS version of JAWS in a DOS Application Window is presented in the next chapter. 4. REMOVING UNNECESSARY HARD DISK FILES Windows needs free disk space on your hard drive for various types of swap files. If you use several large application programs, then you could need up to 16 MB of free disk drive space to support the operation of Windows. If you need to remove files from your hard disk, then you can remove application programs and documents that you do not use. In addition, you can consider removing the following files. 4.1 Files in the \WINDOWS Subdirectory Use the Windows File Manager and the Windows setup program for Removing Unwanted Windows Files from your Windows subdirectory. Carefully consider whether you truly want to remove each set of files before you delete them. If you have any questions about what you are doing, then you should consult the chapter on "optimizing Windows" in your Windows documentation for detailed instruction. Bitmap files with the .BMP filename extension. These bitmap files are used as desktop wallpaper. If you plan to delete these, then use the Windows Control Panel to set wallpaper to "none", before you delete these files. SOL.EXE and SOL.HLP This is the Solitaire game and its Help text. WINMINE.EXE and WINMINE.HLP This is the Minesweeper game and its Help text. PBRUSH.EXE, PBRUSH.HLP, and PBRUSH.DLL This is the Windows Paintbrush accessory, its Help text, and its dynamic-link library. CLOCK.EXE This is the clock accessory. EMM386.EXE This is an expanded-memory emulator. This file can be deleted in situations where you use a different emulator or you do not plan to reconfigure your extended memory. WRITE.EXE and WRITE.HLP This is the Write accessory and its Help text. It is a word processing program. CALENDAR.EXE and CALENDAR.HLP This is the calendar accessory and its Help text. CALC.EXE and CALC.HLP This is the calculator accessory and its Help text. CARDFILE.EXE and CARDFILE.HLP This is the cardfile accessory and its Help text. TERMINAL.EXE and TERMINAL.HLP This is the Windows terminal accessory and its Help text. You can use it with a modem. RECORDER.EXE, RECORDER.HLP, and RECORDER.DLL This is the recorder accessory, its Help text, and its dynamic-link library. It is used to record Windows macros. 4.2 Old Windows Swap Files If you examine the contents of the subdirectory that Windows uses for storing its swap files, then you may find that there are old swap files that can be deleted. These Old Swap Files were most likely left when Windows unexpectedly crashed. Windows normally deletes these files when you exit Windows. Deleting swap files should not be done from within Windows, because you might delete the swap file that is currently in use. Swap files are stored in the TEMP subdirectory. To determine the location of this subdirectory, look in your AUTOEXEC.BAT file for a "SET" statement that indicates the \TEMP subdirectory. This subdirectory was discussed in greater detail in an earlier section of this chapter. You can delete any files in the \TEMP subdirectory that start with the characters "~WOA". These files are application swap files that were created in the standard mode of Windows. You also can delete any file named WIN386.SWP. This file is a temporary Windows swap file created in 386 enhanced mode. This file is usually deleted when you quit Windows, but it can be left on the hard disk when your PC crashes. (You should not delete "386SPART.PAR" or "SPART.PAR".)