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STACKER NOTE                                                   STACKER NOTE
Title: Windows 3.1 and Stacker 
STAC FAX Index #2202 - 4/09/92                          
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Background.

   Stacker and Windows 3.1 are 100% compatible.  This document addresses  
   basic questions and provides guidelines for fine tuning your Stacker-
   Windows configuration.  It covers the Windows Setup program, the use of 
   Virtual Memory Swap Files, and SMARTDRV.EXE.


32-bit disk access and Stacker.

   This feature allows direct disk access while in the 386 Enhanced mode.   
   Windows 3.1 is aware of Stacker drives and will not attempt to access them 
   with this method.  


1. Windows 3.1 SETUP.

     A. It is recommended that you make backup copies of your Config.sys 
	and Autoexec.bat files prior to running SETUP.  If C: is a Stacker 
	drive that is being SSWAPped with its host drive, Windows may make 
	modifications to these files on C: and then copy them to the 
	host drive. This could potentially overwrite the host Config.sys 
	and Autoexec, leaving you without the originals (no backup copies 
	are made). To prepare for this, make sure the Autoexec.bat and 
	Config.sys files are identical on both drives.  
	
	NOTE: Users with the Stacker version 1.x "pointer" Autoexec.bat on C: 
	      should replace it with the "real" one.  The easiest way to do 
	      this is to rename the "pointer" by typing:  
	      REN  AUTOEXEC.BAT AUTO.XXX   
	      Then copy the Autoexec from the host drive to C:.
	
     B. SETUP may modify the Stacker device driver line in the Config.sys.
	This may make your Stacker drives temporarily inaccessible.  If this               
	occurs, just replace Config.sys with a backup copy or reconstruct it 
	if you don't have one.  Refer to the Stacker device driver section in 
	the users manual for more information on the driver syntax.  You may
	locate existing Stacvol files by running FINDVOL from the Stacker
	distribution diskette.
	
     C. If upon reboot your system seems to be caught in a loop, you may have
	two copies of the "pointer" Autoexec.bat pointing at each other. 
	Press <ctrl><break> to halt execution of the Autoexec.bat file.  
	Next, examine the Autoexec.bat on C: and on the host drive to 
	determine if this, in fact, is the case.  If so, restore a backup 
	copy of the "real" Autoexec.bat to both C: and its host drive.    
	
2. Virtual Memory Swap Files.

     A. Permanent and Temporary virtual memory swap files may be established 
	on uncompressed drives.  The size and location of these files can be 
	set in the Virtual Memory section of Control Panel's 386 Enhanced 
	program.  It is possible to create a temporary swap file on a Stacker
	drive by manually adding the parameters to the System.ini file. 
	However, it is generally recommended that the file exist on an 
	uncompressed drive to keep the fragmentation level low in the Stacker 
	drive.
    
     B. In order to create enough free uncompressed disk space, you may have
	to "Shrink" the Stacker drive by running SDEFRAG /G on that drive.  
	Once you have increased the amount of space, you may also have to 
	make it contiguous by running a disk optimization program on the host 
	drive.  Before optimization, unmount the Stacker drive and remove the
	attributes from the associated Stacvol file by running:
	    
	SATTRIB -r -s -h STACVOL.DSK  
	(the name of your STACVOL file may differ).      
 
	Note: SDEFRAG is designed to optimize Stacker drives.  It will not 
	optimize an uncompressed drive.

3. SMARTDRV.EXE.            

     A. Windows may install SMARTDRV.EXE on your system.  SMARTDRIVE works 
	well in a Stacker environment, but only caches the "host" 
	uncompressed drive.  It will not cache the Stacker drive directly 
	and will report that it is "unable to cache the drive" if instructed 
	to do so.  By caching the host drive it is caching compressed data, 
	effectively doubling the size of the cache.   
	
     B. SMARTDRV.EXE and "Replaced Stacker drives".  If you are loading the 
	Stacker device driver into upper memory with QEMM386 or 386MAX and 
	are using SMARTDRIVE to cache replaced drives, you may find those 
	drives inaccessible.  With this configuration it is necessary to 
	mount and replace the drives after SMARTDRIVE has been loaded.  To do 
	this, add an '@' to the Stacker device driver line in the Config.sys
	file for each drive you want to replace.  Then mount the drive in the
	Autoexec.bat after the SMARTDRIVE line with the syntax:

	Stacker x:        where x is the host drive letter.
	
     C. SMARTDRV.EXE and SDEFRAG.  SMARTDRIVE incorporates a "write delay" 
	cache.  It is imperative that caching be turned off for the Stacker 
	drive when SDEFRAG is run.  This can be accomplished by typing:   
	
	SMARTDRV /R d-   where d is the letter of the Stacker host drive.   
	
	Then run SMARTDRV /S to make sure that drive letter is no longer on 
	the list of drives being cached. SMARTDRV may also be disabled by 
	REMarking the line out of the Autoexec.bat file and rebooting.


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Copyright 1993, Stac Electronics                    


