DoubleSpace Drive: Make Directory Results in Zero Bytes Free (106522)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.0
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q106522
This information applies to both Microsoft DoubleSpace and Microsoft DriveSpace. For MS-DOS 6.22, use DRVSPACE in place of DBLSPACE for commands and filenames.


After MS-DOS reports you have several kilobytes (K) free on a DoubleSpace-compressed drive (for example, 128K with a 2:1 estimated compression ratio [ECR]), creating a directory results in zero bytes free disk space.


DoubleSpace reserves some space when a compressed drive is nearly full. Specifically, when the free space in the compressed volume file drops below the 64K uncompressed boundary, DoubleSpace reserves the remaining space for its own use.

For example, if your ECR is 2.0:1 and you have 130K "free" on your drive, you really have 65K left in uncompressed sectors. After you create a directory taking 16 sectors (8K), you have less than 64K free and uncompressed space. As a result, DoubleSpace reserves the remaining space for itself and reports zero bytes free disk space.

Modification Type: Major Last Reviewed: 11/22/1999
Keywords: KB106522