Q82709: SMARTDRV Cache Status – What Does the Buffering Value Mean?
Article: Q82709
Product(s): Microsoft Windows 95.x Retail Product
Version(s): MS-DOS:6.0,6.2,6.21; WINDOWS:3.0,3.0a,3.1,3.11
Operating System(s):
Keyword(s):
Last Modified: 03-OCT-1999
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The information in this article applies to:
- Microsoft Windows versions 3.0, 3.0a, 3.1, 3.11
- Microsoft Windows for Workgroups versions 3.1, 3.11
- Microsoft MS-DOS operating system versions 6.0, 6.2, 6.21
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SUMMARY
=======
In MS-DOS, Windows, and Windows for Workgroups, the character-mode display of
the status of SMARTDrive has a column for buffering status. The entry in this
column can be "yes," "no," or "-" (MINUS SIGN). This article describes the
meaning of these entries.
MORE INFORMATION
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The following is an example of the printout you receive if you access SMARTDrive
from the command prompt by typing smartdrv and pressing the ENTER key:
Microsoft SMARTDrive Disk Cache version 4.0
Copyright 1991,1992 Microsoft Corp.
Cache size: 1,048,576 bytes
Cache size while running Windows: 1,048,576 bytes
Disk Caching Status
drive read cache write cache buffering
--------------------------------------------
A: yes no no
B: yes no no
C: yes yes yes
F: yes yes -
G: yes no no
For help, type "Smartdrv /?"
The column labeled "buffering" describes the state of double buffering. "Yes" in
this column means that double buffering is being performed on the corresponding
drive. "No" means that buffering is not being performed on the corresponding
drive. The state indicated by a MINUS SIGN means that SMARTDRV.EXE cannot
determine if buffering is needed.
SMARTDRV.EXE watches each data transfer to determine the need for buffering. If
it sees a transfer to an upper memory block (UMB), it may be unable to determine
if there is a need for double buffering.
NOTE: The double buffer driver must be loaded for SMARTDRV.EXE to determine if
there is a need for buffering. If the double buffer driver is not loaded, all
entries in the buffering column read "no." The double buffer driver is loaded
from the CONFIG.SYS file. The following is a sample line to install the double
buffer driver:
DEVICE=C:\WINDOWS\SMARTDRV.EXE /DOUBLE_BUFFER
Even if you install the double buffer driver, SMARTDRV.EXE may decide that it is
not needed. In this case, the double buffer driver is not loaded and does not
take up any memory.
You can force the double buffer driver to load even if SMARTDRV.EXE decides that
it is unnecessary. Adding a PLUS SIGN (+), as in the following example, forces
the double buffer to load:
DEVICE=C:\WINDOWS\SMARTDRV.EXE /DOUBLE_BUFFER+
Additional query words: 3.00 3.10 3.11 6.00 6.20 winfest 3.0a
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Keywords :
Technology : kbAudDeveloper kbWin3xSearch kbWFWSearch kbZNotKeyword3 kbWin300 kbWin300a kbWin310 kbWin311 kbWFW310 kbWFW311 kbMSDOSSearch kbMSDOS621 kbMSDOS620 kbMSDOS600
Version : MS-DOS:6.0,6.2,6.21; WINDOWS:3.0,3.0a,3.1,3.11
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