Q107135: Using a RAM Drive to Enhance Performance of DISKCOPY

Article: Q107135
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:6.2,6.21,6.22
Operating System(s): 
Keyword(s): 
Last Modified: 21-NOV-1999

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 6.2, 6.21, 6.22 
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SUMMARY
=======

In MS-DOS 6.2 and later, the DISKCOPY command uses your hard disk drive to
temporarily store the data copied from the source disk. This enables single-
pass disk copies. If you install a RAM drive, you can increase the performance
of this operation.

MORE INFORMATION
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DISKCOPY uses the location defined by the SET TEMP statement to determine where
the data from the source disk should be temporarily stored before it is written
to the destination disk.

If you install a RAM drive and define it as your temporary (TEMP) directory, you
can redirect the data accessed from the source disk into RAM, thus eliminating
the time required for the system to perform read and write operations to the
hard disk drive.

To do this:

1. Set up a RAM drive in your CONFIG.SYS file using the following parameters:

  " device=c:\dos\ramdrive.sys 1480 /e " (without the quotation marks)

  NOTE: Make sure the RAM drive is large enough to hold all data from the
  largest floppy disk drive on your system. (The size given here sets up a
  1.44-megabyte RAM drive.

2. In your AUTOEXEC.BAT file, change the SET TEMP line to point to the RAM drive
  as follows

  " set temp=<x>:\ " (without the quotation marks)

  where <x> is the drive letter assigned by the system to the new RAM
  drive.

The performance gain is not significant on high performance systems with fast
processors and hard disk drives; however, it does increase the overall speed of
this process on older systems.

Additional query words: 6.22 6.20

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS621 kbMSDOS622 kbMSDOS620
Version           : MS-DOS:6.2,6.21,6.22

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