DOCUMENT:Q96552 21-NOV-1999 [msdos] TITLE :What Defragmenter Does & How It Works with 3rd-Party Utilities PRODUCT :Microsoft Disk Operating System PROD/VER:MS-DOS:6.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft MS-DOS operating system version 6.0 ------------------------------------------------------------------------------- SUMMARY ======= Microsoft Defragmenter reorganizes data on MS-DOS drives so that it can be retrieved faster. MORE INFORMATION ================ MS-DOS organizes data on the hard disk into a series of clusters (allocation units) and then tracks which files are using which clusters through directory structures and the file allocation tables (FATs). Neither users nor applications need to know exactly where specific data is located on the hard disk. When an application needs a file, it simply asks MS-DOS to get it. Over time, pieces of files may be spread all over the hard disk. When this occurs, retrieving files requires more time. Defragmenter reorganizes the clusters for faster access. (For example, information is stored at the front of the disk, and parts of files are regrouped together). Defragmenter uses interrupt calls 25H and 26H to move the information stored in one cluster to another, directly updating the FATs and directory structures. Defragmenter operates at nearly the same level as MS-DOS. However, it still uses MS-DOS and is protected from direct interactions with the following: - Third-party partitioning utilities that modify or translate disk geometry (such as Disk Manager and SpeedStor) - DoubleSpace and third-party drive compression utilities Additional query words: 6.00 3rd-party defrag ====================================================================== Keywords : Technology : kbMSDOSSearch kbMSDOS600 Version : MS-DOS:6.0 ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 1999.