DOCUMENT:Q73584  17-DEC-2000  [msdos]
TITLE   :Using Multiple Software Disk Caches Can Destroy Data
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:3.x,4.x,5.x,6.0,6.2,6.21,6.22
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft MS-DOS operating system versions 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0, 5.0a, 6.0, 6.2, 6.21, 6.22 
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SUMMARY
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Using multiple software disk caches concurrently can cause corruption in the
file allocation table (FAT) or in individual files.

MORE INFORMATION
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When running more than one disk cache, information can be thrown from one cache
to another. This can create problems if the code exists in more than one cache
at the time a program is requested. The first cache may intercept and hold
information for later writing, while the second cache may not have all the code
it needs to return the proper data for processing.

Some common disk caches are:

 - PCKwik

 - Icache

 - Ncache

 - Dcache

 - Fast

 - PC-Cache

 - Mcache

The MS-DOS utility FASTOPEN is not a disk cache per se, but instead speeds up
repeat accesses of files. You may find it useful with applications that
repeatedly reopen the same files, such as a database or compiler. In general, a
disk cache will increase performance much more than FASTOPEN.

The products included here are manufactured by vendors independent of Microsoft;
we make no warranty, implied or otherwise, regarding these products' performance
or reliability.


Additional query words: 6.22 3.2 3.20 3.21 3.22 3.3 3.30 3.3a 3.30a 4.0 4.00 4.0a 4.00a 4.01 4.01a 5.00 5.00a 6.00 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS621 kbMSDOS622 kbMSDOS620 kbMSDOS600 kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401 kbMSDOS500a
Version           : MS-DOS:3.x,4.x,5.x,6.0,6.2,6.21,6.22

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