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Next Version of Virtual PC for Mac to Suck Less
Anomalous Coward writes "According to Apple Insider, it seems that the next version of Virtual PC for Mac will at long last have native support for decent graphics cards. Microsoft's XBox development team is developing this shiny new feature. Macs equipped with ATi cards will be able to emulate an original Radeon, while Macs with nVidia cards will be able to emulate a Geforce 3. Since the XBox uses a graphics core based on the Geforce 3, this may explain how Microsoft plans to include backward compatibility for the XBox in the XBox2."
...why they need to _emulate_ the graphics cards? They are the same chip architecture isn't that the same instruction set, why can't they just dump it onto the chip?
Is there anything better than clicking through Microsoft ads on Slashdot?
better still, assuming that you are not using it for testing internet explorer, use 98 lite
Virtual PC is actually pretty fast running on Mac OS Classic on a ~ 500 Mhz G4 or better (it compares very well to a low end entry level Intel notebook certainly), it's just that it's slow on Mac OS X. Obviously now you can't boot newer Mac's in classic it's a problem as under OS X Virtual PC is complete dog. I am really pissed off that the latest G4's don't support Mac OS Classic specifically because I used to like being able to run Windows at a good speed too. I can't help thinking it would have been great on my new 1.5 Ghz PowerBook if only I could boot it into Mac OS Classic...
Virtual PC on Mac OS 9 is an order of magnitude faster on even a 400 MHZ G4 under Mac OS Classic than Virtual PC is on a 1.5 Ghz G4 under OS X. Virtual PC (and OS X) are in need of significant optimising.
I would point out though that the biggest significant factor is RAM. You need to assign the Virtual PC 256 MB of RAM and you want to have 1 GB of RAM in your system. I have 1 GB of RAM in my current PowerBook - without 1 GB of physical RAM and without assigning 256 MB for the Virtual PC itself Windows XP in Virtual PC is fairly unusable.
Windows 98 used to be particularly fast with Virtual PC and the recommended OS. Sadly, something in the switch to Mac OS X made Windows 98 become much slower than Win 2K + under VPC in OS X and that was never addressed. Bascially the situation currently sucks. Now you need 1 GB of RAM, and at it's best it's still 1/4 the speed of VPC on Mac OS Classic.
I think that graphics card emulation is important though. It *really* speeds up the perception and responsiveness of the system, because it lowers the CPU load on your Mac, leaving it free to consentrate on the actual x86 emulation. For the lucky few that had 3D cards back when Virtual PC 3.0 (which *did* have hardware pass through support) you could play Quake at full speed inside Virtual PC.
MS needs to just release a version of windows for the mac that can run as a .app if they want to have real compatibility, but then you'd still have to have a VM for the other x86 applications.
... is far more interesting ...( and along a similar track to what you are suggesting)
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I think that this
nick
Electronic Music Made Using Linux http://soundcloud.com/polyp
This sounds a little like what Apple did during the 68k/PPC transition. Apple wrote an emulation system that allowed Apple to port parts of the OS to PPC at their leisure, while the rest of the OS and legacy apps ran through the emulator. My understanding was that an early PC-on-Mac emulation package (SoftWindows?) tried to do something similar.
The problem with this approach is, since the legacy code is naive about the real hardware it is running on, all the "intelligence" of the coexistence of the two ISAs must be handled in the native code. Early Mac OS's used a "Mixed Mode Manager" as well as a weird "Universal Procedure Pointer" structure to handle context switches and memory accesses. This foundation hung around even after the OS and all current apps were ported to PPC completely, adding unneeded cruft to OS 9. They were finally removed during the transition to OS X and Carbon.
If Microsoft were to try this, VPC users would only get improvements at maybe the UI level, since there is a snowball's chance in Hell that any of the Windows developers would go through the same experience that Mac developers did to support "fat" binaries. This limits speed improvement, since much hardcore processing functionality would still be in x86-land and would require context switches between PPC and x86 on a regular basis.
Those who complain about affect & effect on
While the addition of the virtualized graphics cards will certainly help speedup some operations, I'm curious if the Virtual PC team would be able to make ".NET" applications work better with VPC. It seems that the VPC team could write a "G4" and "G5" CLR JIT compiler, which would be faster than purely trying to emulate the x86 instructions...
Just a thought...
Doh!
For example, VPC would be a -lot- faster if instead of allocating a ton of RAM to VPC, you instead had a VM plug-in for Windows that caused it to ask the emulator (through a trap of some kind) to request RAM from the Mac OS X VM system.
Similarly, if more games and stuff used OpenGL instead of DirectX, they could make OpenGL calls pass straight through to Mac OS X's implementation in much the same way that X11 OpenGL apps do. To some extent, the same tricks could be done with DirectX, I think. That should be a much cleaner solution than trying to mimic a much more limited graphics card.
And I'm surprised VPC (last I checked) doesn't save its working set translations to a cache file that persists across launches. VPC does do working set detection and cached recompilation during execution, right?
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Another poster kind of said this. But what would be really smart would be taking out those features in Windows that ultimately are useless to the Mac user. Don't have a separate desktop and what not, but instead run the OS inside of OS X. Like X11 works, no need for Windows wall paper, just put a task bar on the bottom or side, and label the start button with a VPC logo or something. I would probably buy VPC... maybe, if it weren't simply Windows in a box.
So what's the difference between bytecode (i.e. machine code for the JVM) and Windows EXEs (i.e. machine code for x86 machines) as far as the Mac is concerned?
I did some speed tests on a couple of Windows apps when I upgraded to VPC 6. In both OS 9 and OS X the results were very comparable, compared to VPC 4 or 5 where the OS 9 version blew away the OS X one.
:)
It may be emulating a 300MHz chip, but it'll obviously run faster on the PowerBook
It doesn't mean much now, it's built for the future.
This is interesting...
The article implies that the guy who got fired a year or so ago for posting pictures of a Microsoft loading dock full of Powermac G5s may have been fired not because of petty Mac - Windows jealously (or whatever the explanation was at the time), but because those G5s were a tool for the development for Xbox2.
DO NOT LEAVE IT IS NOT REAL
It's the disk access in XP that's a pig. If you tweak the VPC settings, you can get pretty decent performance out of XP, except where it hits the disk to load programs and swap, then it slows to a pig crawl. Maybe there's some disk features you can tweak in XP to speed up disk access.
I've tweaked my VPC and actually get pretty acceptable performance out of it. I run it on a 1.3 GHz Powerbook with 768 MB of RAM.
I've tweaked it for XP and for Win98. I currently use Win98 because of the lower memory requirements and faster disk access and get speed about equivalent to a 400 MHz PC with no graphics acceleration (no doom 3 guys, but the original Doom, Descent, etc. play fine.).
XP is about the same performance except when the disk gets accessed at which time it slows to a painful crawl.
Here's my tweaking:
I use VPC for playing old Windows games that I still enjoy (alpha centauri, risk) and for running that odd windows program here and there, and this configuration works well for me.
You can tell a great deal about the character of a man by observing those who hate him.
You deserve a mod-up, but since I don't have points, I'll just reply instead to draw attention...
The Mixed Mode Manager came in with System 7.2, which was not really an "early" mac OS - sort of middling.
7.1.2, IIRC. The time it took Apple to reach that from the 128k was about 6-7 years, while the time it took Apple to reach end of the Classic line was closer to ten. From most user's standpoint, System 7 was an "early" Mac OS. (My first Mac ran 7.0.1, but could run 6.0.5, to give an idea of my history here.) Apple quickly gunned through 7 "major" revs (all released for free!) early on, then slowed to only 3-4 revs late in the OS life cycle.
It's interesting, but there is a parallel here with OS X. Apple quickly gunned through 4 major revs (with the first being free), but has announced that Tiger will slow the curve down. I wouldn't be surprised that either Tiger or 10.5 will go down in history as the "System 7" of the OS X legacy.
UPPs weren't "weird", they were in fact a very elegant and inspired piece of design
To most PC developers, "elegant" is "weird." (-;
The notion that a "pointer" wasn't implemented as an memory address, but as a data structure, was a strange thing at that time. (Now-a-days, we just call them "references" and no longer treat memory addresses as something "safe" to work with.) Despite having an easier to grok assembler language, this complication made it harder to write low-level code on the Mac, cementing the need to use a language like C to write all Mac software afterwards. Also, the heavy dependacy on macros in the "Universal Interfaces" to hide UPPs made continued support for Pascal as a application development language difficult.
Those who complain about affect & effect on