Re: Computing Editorial (please read)

[Richard Plinston <riplin@Azonic.co.nz>]

Ross Simpson wrote:

> A lot of water had passed under the bridge between those two Operating
> Systems. That's why whenever you see DRDOS mentioned it's Version 5.xx &
> up. Before that was DOS Plus (which you may have seen included with Gem if
> you were lucky enough to own an Amstrad based PC). Can anyone enlighten me
> what version 3.xx was (Concurrent CP/M-86?)? CP/M-86 v2.x was like CP/M

There was a version 3.x of DR-DOS, but not a version 4 as far as I know.  
DR-DOS 3.41 was very much like MS-DOS 3.3 and did not have the 
multi-tasking kernel or CP/M-86 compatability of DOS Plus, nor the extra 
goodies of DR-DOS 5 and 6.  It did support large drives while MS-DOS 3.3 
only did so in enhanced versions, such as Compaq's and Wyse's.

A few manufacturers, such as IPC, bundled DR-DOS 3.41 with their machines. 
It was a good, competent but boring MS-DOS clone. The only advantage that 
it had was that FDISK could set the cluster size.  I set up several 
business systems using Concurrent-DOS multi-user with accounting type 
applications.  The performance of the larger ISAM files was improved by 
having larger cluster sizes as it reduced the number of FAT entries that 
had to be followed.  Changing from 2Kb to 8Kb clusters improved performance 
of a 1MByte file write, read, random-read test by 3 fold.