Incorrect SMARTDrive BufferSize Setting Hangs System

 Last reviewed: November 21, 1994
Article ID: Q94604
The following information applies to:
  • Microsoft Windows operating system versions 3.1, 3.11
  • Microsoft Windows for Workgroups versions 3.1, 3.11

SUMMARY

SMARTDrive version 4.0, the disk-caching utility supplied with Windows, has a switch, /b:BufferSize, that enables you to change the default size of SMARTDrive's buffer. If this switch contains an invalid entry, the result could hang the system during startup, requiring a boot (system) disk to start the computer.

MORE INFORMATION

SMARTDrive's buffer is separate from the cache. Data is initially transferred to the buffer's memory, then written to the cache in portions, as determined by the /e:ElementSize switch. The default element size is 8192 bytes.

The BufferSize setting is measured in bytes and has a default value of 16K. Page 540 of the "Microsoft Windows User's Guide" states that the valid values for BufferSize can be any multiple of the ElementSize setting. The guide provides no upper limit. However, there is an upper limit on the BufferSize setting based on how much memory is available in the upper memory area (UMA) or in conventional memory.

The valid entries for ElementSize and BufferSize are as follows: 

   If This Value
   Is Used for /e        Use This Value for /b
   ------------------------------------------------------------------

   /e:1024               Multiples of /e up to and including /b:16384
   /e:2048               Multiples of /e up to and including /b:32768
   /e:4096               Multiples of /e up to and including /b:57344
   /e:8192               Multiples of /e up to and including /b:57344
If you attempt to use any other values, you may experience one of the following problems:
  • The system stops responding (hangs).
  • The error message "Sector not found reading drive x" (where "x" is the drive being accessed after SMARTDrive is loaded) appears.
  • The size of SMARTDrive's buffer will not match the BufferSize setting.

For additional information about SMARTDrive, refer to pages 539-541 in the "Microsoft Windows User's Guide."

KBCategory: kbusage
KBSubcategory: win31 wfw wfwg
Additional reference words: 3.10 3.1 smartdrv smartdrv.exe buffer size
crash lock lockup DocErr smart drive

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.

Last reviewed: November 21, 1994
© 1998 Microsoft Corporation. All rights reserved. Terms of Use.