Using SuperStor Disk Compression

 Document 1200

SUPERSTOR

Initials:

        11/26/91

DRDOS 6.0

Keywords:

        SUPERSTOR

        COMPRESSION

        ADDSTOR

Description:

  Using SuperStor Disk Compression

 Installation Tips

The DR DOS 6.0 version of SuperStor recognizes and will operate correctly  

on SuperStor partitions created with the AddStor retail SuperStor  

version 1.3.  The DR DOS 6.0 version of SuperStor was not designed  

to be compatible with other operating systems and should not be expected  

to work properly except with DR DOS 6.0.

Before using SuperStor, backup the data on the drives to be compressed. If  

there is a power failure during the compression, some data could be  

lost.

SuperStor requires that a config.sys file be present on the bootable  

drive to run properly.  If you do not have a config.sys file, you  

can create one using the DR DOS 6.0 Editor.  Use the DR DOS "DEVICE="  

statement to load the SSTORDRV.SYS driver.  SSTORDRV.SYS will  

automatically move into upper memory (through the use of XMS UMBs)  

if space is available.  This is true regardless of whether the XMS  

UMBs are allocated by the DR DOS 6.0 operating system or by a third  

party memory manager.

Determine the maximum amount of uncompressed space you want to leave  

on the disk.  Note that a Windows 3.0 permanent swap file cannot reside  

on a compressed volume.  The actual amount left uncompressed will  

depend on the data compression ratio and the disk space available  

before the compression was done (in other words, SuperStor will use  

as much space as necessary to compress all of your files).

If you are using a disk partitioning utility or removable drive that  

requires a device driver, you might need to experiment to determine  

if that driver should come before or after SSTORDRV.SYS in your config.sys  

file.  The following list is in the correct loading sequence for some  

of the more common of these device drivers:

*DiskManager or SpeedStor partitioning utility drivers should be loaded 

before SSTORDRV.SYS.

*The Bernoulli RCD.SYS driver must be loaded before SSTORDRV.SYS; also, 

to use SuperStor on a bootable Bernoulli cartridge, the RCD.SYS driver 

must be on an uncompressed partition.

*The Plus Hardcard driver must be loaded after SSTORDRV.SYS.

Many customers make a backup bootable floppy diskette in case of unexpected  

problems such as a hard disk controller failure.  After creating a  

SuperStor partition, be sure you update the config.sys file on your  

backup bootable floppy to include the SuperStor driver (and DEVSWAP.COM,  

if required), and copy these files onto the bootable diskette.

SuperStor should typically not be used on a network server, however  

it will work as designed on a workstation drive.

 Troubleshooting SuperStor

The largest partition you can create with SuperStor is 512 Mbytes,  

using a physical partition of 256 Mbytes.  If you have a partition  

larger than 256 Mbytes, you will need to back up your data and use  

the FDISK utility to create smaller partitions before creating a SuperStor  

volume.  

Some customers have reported difficulty installing SuperStor onto  

a second physical hard drive.  This might occur if DOS operating system  

files are present.  Because system files are hidden, a DIR listing  

will not detect them.  Use the command XDIR I*.* to determine if the  

files IBMBIO.SYS or IBMDOS.COM are present.  If they are, use the  

ATTRIB command to remove the system and hidden attributes, then remove  

or rename the system files.

Note:

Do not remove or rename these files on your first physical  

hard drive.

If you accidentally remove the SuperStor partition while the DR DOS  

6.0 DELWATCH utility is active, you might be able to undelete the  

SuperStor partition file, thus restoring the SuperStor partition.

If you use a third party disk optimizer on a SuperStor partition,  

data should not be lost or corrupted.  However, because the third  

party optimizers might not properly recognize the structure of the  

SuperStor partition, they might actually cause worse fragmentation  

than that which existed prior to the optimization process.  Therefore,  

we recommend that you use the DR DOS 6.0 DISKOPT utility, which will  

properly handle the SuperStor partition.