CompuServe Messages

#IPAs

    06-Sep-93 09:45:35
Sb: #56296-#IPAs
Fm: Marion K. Marks 70700,2777
To: Judy Weller 76350,2220
I repeats: we've been using DoubleSpace for months (we were a DOS 6 beta tester, so we've been using it since before DOS 6 was released) on a network of six PCs doing lots of disk access and have had NO corruption of data to date that was traceable to DoubleSpace itself. The problems attributed to DoubleSpace are actually caused by the elevator-seeking write-back caching in SmartDrive, and would happen with Stacker or SuperStor or any other disk compression as well when using any cache that has elevator-seeking write-back caching. Either turn off the write-back caching for the compressed drives, or be sure to flush the cache before powering off ("SMARTDRV /C"), or get DOS 6.2 or the SmartDrive patch available here on CompuServe which upgrades SmartDrive to do an automatic write cache flush whenever a program exits to DOS and before you see the DOS prompt. I won't sit here and see DoubleSpace blamed for things which are not its fault. DoubleSpace is FINE. FINE!! So long as you use the same common sense you would use with floppy disks (don't pull the disk out of the drive when the computer is writing to it — that's the same thing as turning off the computer without flushing the cache), it's FINE. By the way, write caching can also harm NON-compressed drives. It's just more likely to have serious consequences for compressed ones since the loss of a few bytes can render the whole volume unusable by trashing the compression directory. Again, this also goes for Stacker, SuperStor, or ANY other compression technique! The problems that happen when you don't flush the cache on a non-compressed drive are usually limited to "lost chains" and maybe a cross-linked file or two.