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
SMARTDrive will not load after Windows has started.
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]
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
Specifies the location of the SMARTDRV.EXE file.
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.)
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).
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
Up to 1 MB All extended Zero (no caching)
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
Disables write-behind caching for all drives. You can then enable
caching for individual drives by using the drive+|- parameter.
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.
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
Clears the contents of the existing cache, including writing all
write-cached information to disk, and restarts SMARTDrive.
Writes cached data after each command completes. This is the default
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.
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.
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.
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
Displays additional information about the status of SMARTDrive.
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
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.