Virtualization programs. Are they emulators?

[Keatah]

Virtual Box, DOS Box, PCEM, MS Virtual PC 2004/2007 - are all tools one should become familiar with and learn how to use. They're like tunnels or passages through the ever-changing sponge that is modern computing. They're not perfect, but between all four you should be able to get the vast majority of vintage software running on today's hardware. At the correct speeds too. Or at faster more convenient speeds if you're working with technical utilities and file management things.

 

But are they just virtualization programs or emulators? And what what defines the line between virtualization and emulation? Are they just instruction translators? Or real emulators? Do any of these simply re-map x86 instructions from old to new?

 

Whatever they are, and however they do it, they are becoming more important for vintage software enthusiasts as current hardware drifts away from the original IBM PC specifications.

Edited June 14, 2020 by Keatah

[mr_me]

Virtual machines like vmware typically run programs on the native host cpu.  This is not emulation.  Dosbox and Pcem have emulated cpus.

[zzip]

23 hours ago, Keatah said:

Virtual Box, DOS Box, PCEM, MS Virtual PC 2004/2007 - are all tools one should become familiar with and learn how to use. They're like tunnels or passages through the ever-changing sponge that is modern computing. They're not perfect, but between all four you should be able to get the vast majority of vintage software running on today's hardware. At the correct speeds too. Or at faster more convenient speeds if you're working with technical utilities and file management things.

 

But are they just virtualization programs or emulators? And what what defines the line between virtualization and emulation? Are they just instruction translators? Or real emulators? Do any of these simply re-map x86 instructions from old to new?

 

Whatever they are, and however they do it, they are becoming more important for vintage software enthusiasts as current hardware drifts away from the original IBM PC specifications.

Technically, if it emulates the CPU, it's an emulator.  If it executes code on your actual CPU than it's virtualization

 

Dosbox is an Emulator,  PCEM is an emulator.   Virtual PC/Virtualbox, etc are Virtualization

 

Virtualization is faster, but tends to have trouble with the older line of Windows like Win95/98/ME.   But I can get them running on Dosbox

Edited June 15, 2020 by zzip

[Keatah]

Yikes! Win98 or ME on DosBox? I only tried up to Win 3.1 there.

 

I'd think that virtualization would be better for Win98??

[zzip]

5 minutes ago, Keatah said:

Yikes! Win98 or ME on DosBox? I only tried up to Win 3.1 there.

 

I'd think that virtualization would be better for Win98??

I have 95 running on Dosbox, and it works pretty well-  that OS only needed a 386/486 so Dosbox is fine.   I'd prefer to have 98 running under virtualization, but haven't found a virtualization package that supports it well.   Remember that the pre-XP consumer Windows were built on the crappy Windows legacy codebase, which apparently doesn't play well with modern virtualization while XP was built on the newer NT codebase

[mr_me]

The problem with virtualising old operating systems on modern hardware is compatibility.  Even if the cpu is backwards compatible, there could be issues with bios, chip sets, audio chips, etc.  Emulation solves all those problems.  Windows XP is not as old as Windows 98 and was supported on the latest hardware for a long time.  Try installing Windows 2000 or Windows NT 4 on a modern computer.  Virtualisation is really meant for running multiple instances of compatible operating systems on one computer.

Edited June 16, 2020 by mr_me

[Minuous]

I have never heard A-Max be considered to be anything than an emulator, but it doesn't do CPU emulation. So running guest code directly on the host without CPU instruction translation does not necessarily mean something is not an emulator.