◄Notes►  ◄Examples►
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                                  SMARTDRV
 
Starts or configures SMARTDrive, which creates a disk cache in extended
memory. A disk cache can significantly speed up MS-DOS disk operations. When
used for disk caching, SMARTDrive is loaded by using the SMARTDRV command in
your AUTOEXEC.BAT file or at the command prompt.
 
SMARTDrive can also perform double buffering, which provides compatibility
for hard-disk controllers that cannot work with memory provided by EMM386 or
Windows running in 386 enhanced mode. To use double buffering, load the
<SMARTDRV.EXE> device driver by using a DEVICE command in your CONFIG.SYS
file.
 
SMARTDrive will not load after Windows has started.
 
Syntax
 
When starting SMARTDrive from your AUTOEXEC.BAT file or from the command
prompt, use the following syntax:
 
    [drive:][path]SMARTDRV [/X] [[drive[+|-]]...] [/U] [/C|/R] [/F|/N] [/L]
    [/V|/Q|/S] [InitCacheSize[WinCacheSize]] [/E:ElementSize]
    [/B:BufferSize]
 
Once SMARTDrive is running, use the following syntax:
 
    SMARTDRV [/X] [[drive[+|-]]...] [/C|/R] [/F|/N] [/Q|/S]
 
To view the current status after SMARTDrive has loaded, use the following
syntax:
 
    SMARTDRV
 
Parameters
 
[drive:][path]
    Specifies the location of the SMARTDRV.EXE file.
 
[[drive+|-]
    Specifies the letter of the disk drive for which you want to control
    caching. Include the plus (+) sign to enable caching for the specified
    drive; include the minus (-) sign to disable caching for that drive. You
    can specify multiple disk drives.
 
    If you specify a drive letter without a plus or minus sign, read-caching
    is enabled and write-caching is disabled. If you specify a drive letter
    followed by a plus sign (+), read-caching and write-caching are enabled.
    If you specify a drive letter followed by a minus sign (-), both
    read-caching and write-caching are disabled. If you don't specify a
    drive letter, floppy disk drives, CD-ROM drives, and drives created
    using Interlnk are read-cached but not write-cached, hard disk drives
    are both read-cached and write-cached, and network drives and Microsoft
    Flash memory-card drives are ignored. (For information about how
    DriveSpace caches compressed drives, see Notes.)
 
InitCacheSize
    Specifies the size in kilobytes of the cache when SMARTDrive starts
    (when Windows is not running). The size of the disk cache affects how
    efficiently SMARTDrive runs. In general, the larger the cache, the less
    often SMARTDrive needs to read information from the disk, which speeds
    up your system's performance. If you do not specify an InitCacheSize
    value, SMARTDrive sets the value according to how much memory your
    system has (see the table below).
 
WinCacheSize
    Specifies, in kilobytes, how much SMARTDrive will reduce the cache size
    for Windows. When you start Windows, SMARTDrive reduces the size of the
    cache to recover memory for Windows' use. When you quit Windows, the
    cache returns to its normal size. WinCacheSize specifies the smallest
    size to which SMARTDrive will reduce the cache. The default value
    depends on how much available memory your system has (see the table
    below). If you specify a value for InitCacheSize that is smaller than
    the value specified for WinCacheSize, InitCacheSize is set to the same
    size as WinCacheSize.
 
The following table shows what the default values for InitCacheSize and
WinCacheSize will be, depending on the amount of available extended memory
your computer has.
 
Extended         InitCacheSize        WinCacheSize
Memory
───────────────────────────────────────────────────────────────────────────
 
Up to 1 MB       All extended         Zero (no caching)
                 memory
 
Up to 2 MB       1 MB                 256K
 
Up to 4 MB       1 MB                 512K
 
Up to 6 MB       2 MB                 1 MB
 
6 MB or more     2 MB                 2 MB
 
Switches
 
/X
    Disables write-behind caching for all drives. You can then enable
    caching for individual drives by using the drive+|- parameter.
 
/U
    Does not load the CD-ROM caching module of SMARTDrive even if you have a
    CD-ROM drive. If SMARTDrive is loaded with the /U switch, you cannot
    enable CD-ROM drive caching. If SMARTDrive is loaded without the /U
    switch, you can disable or enable caching individual CD-ROM drives using
    the drive+|- parameter.
 
/C
    Writes all cached information from memory to cached disks. SMARTDrive
    writes information from memory to the disk at times when other disk
    activity has slowed. You might use this option if you are going to turn
    off your computer and want to make sure all cached information has been
    written to the disk. (SMARTDrive writes all cached information to the
    disk if you restart your computer by pressing CTRL+ALT+DELETE, but not
    if you simply turn off the power or press your computer's reset
    button.)
 
/R
    Clears the contents of the existing cache, including writing all
    write-cached information to disk, and restarts SMARTDrive.
 
/F
    Writes cached data after each command completes. This is the default
    value.
 
/N
    Writes cached data when the system is idle. When the command prompt
    returns, not all cached data may be written yet. To ensure that all the
    cached data is written, use the /C switch.
 
/L
    Prevents SMARTDrive from automatically loading into upper memory blocks
    (UMBs), even if there are UMBs available. You can use the /L switch if
    upper memory is enabled for use by programs. If you are using
    SMARTDrive's double-buffering feature and your system appears to be
    running slowly, try adding the /L switch to the SMARTDrive command in
    your AUTOEXEC.BAT file.
 
/V
    Instructs SMARTDrive to display status and error messages when it
    starts. (By default, SMARTDrive does not display any messages unless it
    encounters an error condition.) The /V switch cannot be used in
    conjunction with the /Q switch.
 
/Q
    Instructs SMARTDrive not to display status messages when it starts. (By
    default, SMARTDrive does not display status messages when loading, but
    does for most other operations.) If SMARTDrive encounters an error while
    starting, it displays an error message whether or not it was loaded with
    the /Q switch. The /Q switch cannot be used in conjunction with the /V
    switch.
 
/S
    Displays additional information about the status of SMARTDrive.
 
/E:ElementSize
    Specifies in bytes the amount of the cache that SMARTDrive moves at a
    time. Valid values are 1024, 2048, 4096, and 8192. The default value is
    8192. The larger the value, the more conventional memory SMARTDrive
    uses.
 
/B:BufferSize
    Specifies in bytes the size of the read-ahead buffer. A read-ahead
    buffer is additional information that SMARTDrive reads when an
    application reads information from the hard disk. For example, if an
    application reads 512K of information from a file, SMARTDrive then reads
    the amount of information specified by BufferSize and saves it in
    memory. The next time the application needs to read information from
    that file, it can read it from memory instead. The default size of the
    read-ahead buffer is 16K (16384 bytes). Its value can be any multiple of
    ElementSize. The larger the value of BufferSize, the more conventional
    memory SMARTDrive uses.
 
Caution:  Check that SMARTDrive has completed all write-caching before you
          restart  or turn off your computer. (This is not necessary if you
          restart your computer by pressing CTRL+ALT+DELETE.) To have
          SMARTDrive write all cached information to cached disks, type
          SMARTDRV /C at the command prompt. After all disk activity has
          stopped, you can safely restart or turn off your computer.
 
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