Windows 3.1X On Pandora

[Monk]

Here's another way of looking at the probable speed of Windows 3.x under DOSBox on the Pandora. From one of darkborn's links:

http://members.chello.at/theodor.lauppert/games/wolf3d.htm

The requirements of Wolf3D is given as:


System Requirements
The system requirements of the original PC version are astonishingly low. For fluent gameplay on a slower computer, reduce the window size. I've played it on a 10 MHz 286 with 5MB RAM with enjoyment. For maximum window size, you will need something faster. On DOSBox, it will play well with the default 3000 CPU cycles.

Or from the official website where you can still buy it:

SYSTEM REQUIREMENTS

286 Computer (386+ Strongly Recommended)

Now, Pickle had to overclock the Pandora by 100MHz up to 600MHz to get Wolf3D running at 2000 cycles without sound. So DOSBox on the Pandora, even overclocked, was struggling to play a game that has a 286 as a minimum requirement.

It beggars belief but it appears that DOSBox is REALLY slow on the Pandora (to be honest, it always feels incredibly slow on a multi-GHz x86 PC trying to emulate an x86 PC - but on the Pandora, which has a different CPU architecture, the slowdown seems magnified).

Pickle's also gone on record repeatedly saying that DOSBox isn't going to get MUCH faster than it is already on the Pandora. I tend to trust Pickle a fair way on that, given the other work he's done. So we're looking at being able to emulate a PC at very low specs - 286/386 kind of speeds not 486/Pentium kind of speeds.

I dug out a Symantec pack of games for Windows 3.x the other day - who'd have thought it? I may well try installing Win3.X on DOSBox and/or Virtual PC one of these days on my desktop.

 

[darkborn]

DOSBox is not going to emulate an x86 at 500 or 600MHz!

You're flamer or what? We all agree that it will not run (DOS emulation) at 500MHz.

It'll be closer to a 386 at maybe 16MHz from the numbers we're seeing right now.

However, I think when DOSBox become fine tuned, it could achieve something like 386@50MHz - 486@25MHz. Which is quite enough.

QEMU + Wine would not be 20-50% in performance, I don't know why you think that. It'll probably be substantially faster. DOSBox for ARM is slow.

HERE is wine+qemu topic at sister forum, read it carefully. QEMU is great emulator, it is just that it is not yet ported. At least, not in a state for common use. "Generic" port of QEMU (like actual of DOSBox) will not bring us much more performance.
Here is document about current attempt of porting RISC-OS to ARM Cortex-A8/OMAP3530 with QEMU@OMAP3 links. Study yourself.
Wine is different story. Wine does not emulate CPU: instead it uses native x86 cpu calls (provided from bochs, qemu...) and just translates the windows api calls to display graphics. Don't expect that Wine will be ported to ARM. Just, you don't have to emulate whole Win API with Wine to run 16-bit Windows application. So, it is possible to make some hybrid/tweaking of Wine which will bring us more speed. But it is all theoretical. Let us see real hardware in action.
If we talking about compatibility, QEMU+Wine will be superior. If we talking about speed, right now DOSBox is better (and right now only one) solution.

 

[Pleng]

DOSBox is not going to emulate an x86 at 500 or 600MHz!

You're flamer or what? We all agree that it will not run (DOS emulation) at 500MHz.

It'll be closer to a 386 at maybe 16MHz from the numbers we're seeing right now.

However, I think when DOSBox become fine tuned, it could achieve something like 386@50MHz - 486@25MHz. Which is quite enough.

It's been repeatedly said that there is very little room for optimisation in DosBox short of a complete rewrite, it's certainly not going to treble in speed as you seem to hope.

 

[Archaemic]

Calling Exophase a flamer? I wouldn't recommend that...

Anyway, I saw someone playing a DOSBox game recently on his fairly modern laptop, and that was painfully slow. He said it ran about the same speed on his old DOS computer.

 

[ldesnogu]

HERE is wine+qemu topic at sister forum, read it carefully. QEMU is great emulator, it is just that it is not yet ported. At least, not in a state for common use. "Generic" port of QEMU (like actual of DOSBox) will not bring us much more performance.

Two questions: what is a "generic" port of QEMU vs a non-generic? What makes you think a generic port won't bring much performance (here I assume against DOSbox)?

If we talking about compatibility, QEMU+Wine will be superior. If we talking about speed, right now DOSBox is better (and right now only one) solution.

What makes you think so? First hand experience?

 

[darkborn]

HERE is wine+qemu topic at sister forum, read it carefully. QEMU is great emulator, it is just that it is not yet ported. At least, not in a state for common use. "Generic" port of QEMU (like actual of DOSBox) will not bring us much more performance.

Two questions: what is a "generic" port of QEMU vs a non-generic? What makes you think a generic port won't bring much performance (here I assume against DOSbox)?

Look at QEMU host status: http://www.qemu.org/status.html: ARM port is still in "testing" phase.
It means even if it works (ARM generic, ARMv7 e.g. Cortex), it is not ready or optimized as it could/should be (e.g. for OMAP 3503 chipset). By "generic port" I meant just like that. "Non generic" means optimized, by performance (speed) as a first. And when you are talking about performance, you are probably thinking about KQEMU accelerator, which is quite impressive. I'll disappoint you: this is only for emulating x86 PC on an x86 host, not ARM.
KQEMU will not happened soon at ARM (if ever).
"I'll note that it's hard to provide good support for ARMv7 in general as the architecture documentation is not publicly available." (from qemu developers forum) (OT: Here is Comparison of platform VM for interested.)
Conclusion will be: In theory, it is easier to emulate just simple OS with some known hardware interrupts included (like DOSBox), then whole hardware architecture/configuration on top of (still partly unknown) another (like QEMU/Bochs/etc).
Moreover, you don't have to emulate whole Win 32-bit API (like Wine usually do) for running 16-bit windows applications (which are mostly "GUI based" DOS applications).
But because DOSBox@ARM sucks, it is possible that QEMU "overperform" it. DOSBox is not ported very well at ARM architecture.
As Pickle said: "Although dosbox has the ability to recompile parts of the x86 code to ARM, although it wouldnt be a fast if someone wrote a x86 to ARM recomplier backend." http://forum.openhandhelds.org/viewtopic.php?p=405#p405
DOSBox cycles=3500-4000@PSP@222/333MHz http://forum.openhandhelds.org/viewtopic.php?p=458#p458 ; DOSBox cycles=2000-3000@Pandora@400-900MHz http://www.gp32x.de/board/index.php?/topic/44801-fallout-in-dosbox/page__view__findpost__p__659398

What makes you think so? First hand experience?

Nope. How about simple logic? Read ahead statements above so many times as you need.

 

[darkborn]

However, I think when DOSBox become fine tuned (...)

It's been repeatedly said that there is very little room for optimisation in DosBox short of a complete rewrite (...)

It is just like I said.
It is "ARM (OMAP) explosion" what should we expect: seems to me it will be some of the most important hardware things happened at 2009. Involved players are Google, Nokia, Apple... just name it. Logic consequence is to get proper DOSBox port.
However:
DOSBox cycles=3500-4000@PSP@222/333MHz; DOSBox cycles=2000-3000@Pandora@400-900MHz (for now): 2000-up is, roughly, 386@20MHz-up to (...) It is just as Windows 3.1 requirements are - look at this video http://www.youtube.com/watch?v=D9jNvScJ8w8
Notice that it needs just a few seconds to "boot" Windows (from DOS), but for everything else much more. It is probably because of <16MB RAM (& swap file). Pandora can provide as much RAM (or swap=virtual RAM) as needed.

 

[darkborn]

Now, Pickle had to overclock the Pandora by 100MHz (???) up to 600MHz to get Wolf3D running at 2000 cycles without sound. So DOSBox on the Pandora, even overclocked, was struggling to play a game that has a 286 as a minimum requirement.

Pandora: Warcraft 2 (http://www.codejedi.com/cgi-bin/blog.cgi/entertainment/gaming/pandora/20081221wc2dosbox.blog)
"This is a stock DOSBox (by which I mean compiled from source, with no optimizations _at all_, and not even tuning the config. Its got the wrong cycle settings and full audio enabled and installed _from my Warcraft 2 ancient CD_. DOSBox in dynarec mode though, so its working its ass off here The good news -- runs nearly full speed, and fully playably. I've worked through the first Orc campaign mission. USB mouse and keybord." (...)
"Pandora was set to 800MHz .. and the Panda can go higher still; I probably should've tried for 900 or more" (...)
It sounds great, I just don't know is this guy serious/relevant.
Warcraft II official requirements: "Pentium 60 or equivalent (...)" (ofcourse it's bs) but it is probably Intel 386 20 MHz or faster (...).

It beggars belief but it appears that DOSBox is REALLY slow on the Pandora (to be honest, it always feels incredibly slow on a multi-GHz x86 PC trying to emulate an x86 PC - but on the Pandora, which has a different CPU architecture, the slowdown seems magnified).

I agree with that 100%, my experiences are the same. However, seems to me that it is forgotten how low system requirements were before WINTEL & co started to push it... before OLPC (etc) shows us that's nonsense.

Pickle's also gone on record repeatedly saying that DOSBox isn't going to get MUCH faster than it is already on the Pandora. I tend to trust Pickle a fair way on that, given the other work he's done. So we're looking at being able to emulate a PC at very low specs - 286/386 kind of speeds not 486/Pentium kind of speeds.

Well that depence of the case. Digital sound, 3d graphic, high res animation... yep, it will look probably like 286. IMO opinion it should act like 386SX 20MHz up at Win3.X case. 2000 cycles or so.

I dug out a Symantec pack of games for Windows 3.x the other day - who'd have thought it? I may well try installing Win3.X on DOSBox and/or Virtual PC one of these days on my desktop.

PLEASE, DO! I just don't have time to do it properly. Please, take a look at cycles (I think that info could be turned on constantly).
Here are some guides to help:
Windows 3.1x in DOSBox guide (semi-official @VOGONS), Win3.1 install at DOSBox (psp) There are plenty of video guides at youtube.