Q94023: MS-DOS Kernel Is Larger Than 60K

Article: Q94023
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.0
Operating System(s): 
Keyword(s): 
Last Modified: 21-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system version 5.0 
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SUMMARY
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The Microsoft MS-DOS MEM command (MEM /C) reports an unusually large size for
the MS-DOS kernel under the following two conditions:

- You are creating a large number of buffers in the CONFIG.SYS file.

- You have a virus.

MORE INFORMATION
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The MS-DOS 5.0 kernel (simply displayed as "MS-DOS" by MEM) usually occupies
approximately 60K of conventional memory. If you load more than 48 buffers, or
if you do not load MS-DOS high, the buffers load in conventional memory, causing
the MS-DOS kernel to grow.

For example, increasing the "buffers=" setting in the CONFIG.SYS file from 40 to
60 increases the size of the MS-DOS kernel by 20K. This growth occurs because
each additional buffer takes up approximately 532 bytes of memory, and once the
value for buffers= is increased above 48, all the buffers load into conventional
memory.

Note: One buffer is always loaded into conventional memory, so the number of
buffers actually loaded into the high memory area (HMA) is one less than the
number of buffers specified.

If the buffers= setting is not causing the kernel to increase in size, you may
have a virus, such as one that attaches itself to COMMAND.COM. To determine if
this is the case, you can obtain virus-scanning software from many third-party
vendors.

For more information on memory management, query on the following words in the
Microsoft Knowledge Base:

  " ms-dos and buffers and uma " (without the quotation marks)

Additional query words: 3.10 5.00 large dos

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS500
Version           : MS-DOS:5.0

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