MS-DOS Kernel Is Larger Than 60K (94023)


The information in this article applies to:
    • Microsoft MS-DOS operating system 5.0
This article was previously published under Q94023

SUMMARY

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

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

Modification Type: Major Last Reviewed: 11/21/1999
Keywords: KB94023
©2002 Microsoft Corporation. All rights reserved.