LP> At the moment, I use Reconfig to boot different DOS configurations
 LP> because if I had a universal set up I would not be able to run hardly
 LP> anything.

A utility like RECONFIG, as described (assuing that the double negative was an 
error (-:), won't be necessary for OS/2.  This is for three reasons.

The first is that unlike DOS, OS/2 doesn't have to cram everything into 640KiB 
of conventional RAM.  The problem with DOS is that loading device drivers
affects the amount of memory available to applications.  OS/2 is a virtual
memory operating system that uses protected mode, and this problem simply
doesn't occur.  Yes, if one loads too much into kernel address space it will
consume a fair amount of physical RAM, but this will just mean that
applications will run more slowly because the operating system will have to
swap them to and from the swapfile more often.  On DOS, too little physical
memory can stop applications from even loading, because device drivers and
applications "see" the same address space.  This is not the case with virtual
memory operating systems like OS/2 Warp.  Applications cannot "see" device
drivers in memory.  Loading device drivers doesn't reduce the amount of
address space that is available to applications.

The second reason is that the amount of physical memory consumed by device
drivers is not the main thing to worry about anyway.  It's actually quite
difficult to get to the stage of "too much" loaded into physical RAM as
described in the preceding paragraph.  If one looks at most of the device
drivers in the \OS2\BOOT directory, most of them are only a few KiB in size
anyway, and their in-memory "footprints" aren't much larger than the file
sizes.  The *major* consumers of memory are *other applications*, and the
amount of *virtual* memory that they consume.  The Workplace Shell, for
example, has quite a high working set size (the amount of pages of its virtual 
memory image that it needs to be present in physical memory in order to keep
running at a reasonable speed without paging all of the time).  Back in the
days of machines with 4MeB of RAM, it was recommended to use something other
than Workplace Shell as one's shell, since with such a small amount of
physical RAM WPS, as it ran, would cause the system to page to and from the
swapfile at a furious rate.  It is worth noting, however, that generally one
*didn't* have to worry about device drivers, even on such machines.  In
comparison to the impact of large *applications* like Workplace Shell (or
Netscape, or SmartSuite, or StarOffice, or the Java VM, or ...), the impact of 
loading a large number of OS/2 device drivers on system peformance is quite
small.  About the only other thing that generally one needed to address on
such 4MeB machines was the cache sizes for the FAT and HPFS filesystem
drivers.  Even with 4MeB machines, therefore, one can pretty much load all
device drivers all of the time.

The third reason is that OS/2 already has a "multiboot" facility built in,
should that be necessary, which selects amongst alternate CONFIG.SYS files at
boot time if one presses [ALT-F1].  Indeed, as standard one is supplied with
several alternate boot configurations for performing system maintenance and
repair.  One can boot to a "Maintenance Desktop" with the display running in
VGA mode if the default Desktop is unusable.  One can make archives of one's
desktop at any point and boot to the last three archives made.  One can boot
to text mode where no graphics drivers are loaded if one has misconfigured
one's graphics drivers.  The on-line documentation describes in detail how one 
can extend the multiboot menu with more configurations if one needs them.  But 
remember that, as per the first and second reasons, one generally *doesn't*
have to do this.  The notion of playing musical CONFIG.SYS files and rebooting 
is something that you'll have to largely "unlearn" when moving from DOS to
OS/2.

 ¯ JdeBP ®

--- FleetStreet 1.22 NR
500/3