Best machine for PPC emulation

[Marmotta]

I have in project to assemble a budget machine only for emulation... Goal is low budget and maximum speed!

But I have some questions: on the web are present different opinions... Emulation use only one core? Is the minimum to have two core? Quad or more core is the best???? Amd or Intel? More clock or more cache?

On the web is not present a comparative benchmarks (it would be interesting), I know is true the emulation use only one core, but... I have see my system monitor when I run Os4 on UAE and all four cores run very busy! Why?

Where is the truth?

[Aegis]

Originally Posted by Marmotta

Where is the truth?

It's out there

First you should know that irrespective of the PC you build you're not going to get more than SAM440-460-ish PPC performance out of UAE - worse still, there's no hardware accelerated 2D/3D at the moment (though that may change) so a lot of stuff (games) either won't run at all or they'll be slow in comparison to real hardware - here's Quake for example on an i7:

Quake @ 320x200 WB3.9 68k = 272fps
Quake @ 320x200 OS4.1 PPC = 28fps

Lastly, memory is very tight at the moment - OS4.1 Classic runs nicely on an emulated Cyberstorm PPC but that only provides 128MB of RAM. You can do a *lot* with that - more than you might think - but many apps and games need more than that, further limiting what you can do.

Now, all that said I'm having a blast running OS 4.1 Classic on an i7 - it's perfectly usable for many things - even some games. If you do build a machine for this you'll want the fastest Intel i5 or i7 you can afford. Graphics card isn't so important (I use an AMD R285) but why build a fast PC if you're not going to put a good GFX card in there?

WinUAE does use multiple cores even though the PPC emulation only uses one since it's emulating far more than just the CPU.

[Marmotta]

Yes I know the actual limitations, but the answer remains... In practice on os4 is faster an i3 dual core clocked at 4ghz or 12 core 2ghz Opteron? Winuae use all 12 core? Or use 11 core for emulation and only one core for quemu?

Two or four core of the same cpu make difference?

[Toni Wilen]

Quake? Not again! It is practically pure FPU test and FPU is softfload (full software emulation) emulated in QEMU. FPU is only important if you want to run ports of PC programs.

Max 2 generations old fastest clock rate possible Intel CPU with at least 2 cores and largest cache is the only correct choice for emulators And do not choose slowest possible memory (1-2 higher speed grade is fine, anything faster is mostly pointless)

You want as good as possible single core performance. Single core emulated CPU performance can't be improved with multiple physical CPU cores. It does not work that way. It can't be parallelized.

[Aegis]

Toni would have to answer that but I *think* I saw him mention that WinUAE uses up to 5 cores (although it won't max any of them) - not sure whether HyperThreading provides any benefits to WinUAE.

Personally, I wouldn't recommend either of your suggestions and since money is a factor I'd suggest the best i5 you can buy.

*Edit* Toni beat me to it

Originally Posted by Toni Wilen

Quake? Not again! It is practically pure FPU test and FPU is softfload (full software emulation) emulated in QEMU. FPU is only important if you want to run ports of PC programs.

Then it's a perfect example for people not to expect miracles even on a fast PC

[Marmotta]

Originally Posted by Aegis

Toni would have to answer that but I *think* I saw him mention that WinUAE uses up to 5 cores (although it won't max any of them) - not sure whether HyperThreading provides any benefits to WinUAE.

Personally, I wouldn't recommend either of your suggestions and since money is a factor I'd suggest the best i5 you can buy.

*Edit* Toni beat me to it

Toni say the best is dual core... If is correct the best cpu is i3 at high clock and fast memory. I5 is all quad core.

Because in my main system (i5) uae use all four cores? (i see it in system monitor)

Sorry if I not understand all... English is not my language :-)

[Aegis]

Originally Posted by Toni Wilen

Max 2 generations old fastest clock rate possible Intel CPU with at least 2 cores and largest cache is the only correct choice for emulators

My emphasis

*Edit* I just ran a quick test and WinUAE b7 is hitting 5 cores out of 8 (4 HyperThreaded) on my i7 965.

[jbenam]

Originally Posted by Marmotta

Toni say the best is dual core... If is correct the best cpu is i3 at high clock and fast memory. I5 is all quad core.

Because in my main system (i5) uae use all four cores? (i see it in system monitor)

Sorry if I not understand all... English is not my language :-)

You need to look for the CPU with the highest IPC (Instructions per Clock) as it means they're faster at doing the same things than other CPUs.

http://www.anandtech.com/show/9483/i...h-generation/9

The Core i7 6700K sounds like a winner - even better if you overclock it

Get the fastest DDR4 you can get and enjoy - obviously you'll also need a decent motherboard to go along with it, getting an i7 and then slapping it on a 60EUR motherboard is going to kill any performance advantage you might see

[Toni Wilen]

Originally Posted by Aegis

Then it's a perfect example for people not to expect miracles even on a fast PC

Perhaps but you compared it with emulation that uses host FPU, not softfloat. It simply was not good comparison. It is tricky, especially in emulation, to find benchmark that returns result that actually tells about real peformance and not speed of some super-fast special case or bottleneck..

I just ran a quick test and WinUAE b7 is hitting 5 cores out of 8 (4 HyperThreaded) on my i7 965.

Did it really use them or was it just jumping between cores? Each trap also uses thread for very little time that may explain it, especially if you don't see it when not using UAE expansions.

I forgot about that.. So 4 cores is probably better option with UAE expansions. (at least with current implementation)

then slapping it on a 60EUR motherboard is going to kill any performance advantage you might see

Performance differences are quite small between models, at least with quality big-name manufacturers. Main differences are number of and quality of onboard devices (like cheapest and crappies possible realtek audio and lan..) and overclocking/memory speed options.

[jbenam]

Originally Posted by Toni Wilen

Performance differences are quite small between models, at least with quality big-name manufacturers. Main differences are number of and quality of onboard devices (like cheapest and crappies possible realtek audio and lan..) and overclocking/memory speed options.

Maybe I was thinking of older times, when cheaper motherboards usually had crappier buses and limited memory interfaces when compared to higher-end models.

Good to know!

[Toni Wilen]

Originally Posted by jbenam

Maybe I was thinking of older times, when cheaper motherboards usually had crappier buses and limited memory interfaces when compared to higher-end models.

Yes and manufacturers probably would still do it. But they can't..

Memory controller and most other bus controller stuff that was in separate chip ("north bridge") is now inside the CPU.

[Aegis]

Originally Posted by Toni Wilen

Perhaps but you compared it with emulation that uses host FPU, not softfloat. It simply was not good comparison. It is tricky, especially in emulation, to find benchmark that returns result that actually tells about real peformance and not speed of some super-fast special case or bottleneck..

Yes - it's really hard to make objective comparisons - particularly for someone less technical such as myself Personally I think the OS4 support as a whole is an incredible achievement and very usable but I wouldn't recommend someone build a PC specifically for just that

Originally Posted by Toni Wilen

Did it really use them or was it just jumping between cores? Each trap also uses thread for very little time that may explain it, especially if you don't see it when not using UAE expansions.

Consistent usage over 5 cores for OS4 for the test I did running Doom and Hexen and playing an mp3 from a shared drive (I'm only using Win 8.1 Task Manager to observe it though)

[johnim]

i have emulated os4.1fe on a core dueo 2.6ghz at full speed no problem with a 8800gs and 2gb ram

[Aegis]

Originally Posted by johnim

i have emulated os4.1fe on a core dueo 2.6ghz at full speed no problem with a 8800gs and 2gb ram

What exactly does 'full speed' mean though? I wouldn't call my setup (i7 965 3.3GHz, 12GB DDR3 RAM, AMD R285) 'full speed' since a newer CPU/motherboard, overclocking etc. would be even full speedier

Ideally we'd be able to take full advantage of OS4 which means full SAM460ex performance including hardware-accelerated 2D/3D and 2GB+ RAM but that's not currently possible - if your comparison is the CSPPC without a graphics card then yeah - WinUAE smokes it but that hardware configuration isn't what I'd consider 'usable' for OS4.

I do run WinUAE/OS4 on my 1.7GHz i3 laptop though and it works and it's fun but it's also predictably quite slooow in comparison.

*Edit* I captured a little video running on the i7 a while back: https://www.dropbox.com/s/nckoxvxwh3..._AOS4.mp4?dl=0

[Marmotta]

it would be interesting a dual-core vs quad-core speed comparison on os4... we post a benchmark? (sysmon?)

[Marmotta]

I do some test :-)

I have fs-uae (same winuae core) with my motherboard I can select number of cores.

i5 3570K

- 4 core: Sysmon ragemem mips variable to 2800 to 3000
- 2 core: fast! No difference than four cores, sysmon ragemem mips variable to 2800 to 3000
- 1 core: slow.... very slow! Unusable. I not have patience to launch sysmon :-)

[Marmotta]

Boot time:

- 4 core: 37 seconds
- 2 core: 48 seconds

Four is better?

[Marmotta]

Real use of AmigaOs4.1

- 4 core: browsing is acceptable and scrolling is smooth, if I have some drawers opened on workbench all moves very smooth

- 2 core: browsing is acceptable but scrolling is slow... If I have one drawer open on workbench it moves smooth, but if I have some drawers opened all go slow.

Ok quad is very better than dual! And now.... why?

[Tomislav]

Maybe Windows system + programs in background + WinUAE + Qemu (PPC). It's normal that 4 cores acts better than 2.

[Marmotta]

Originally Posted by Tomislav

Maybe Windows system + programs in background + WinUAE + Qemu (PPC). It's normal that 4 cores acts better than 2.

My test is with osx and first to start uae I have all cpu at full idle.

It seems that uses one cpu for PPC emulation, one for the disk, one for the graphics and one for..... ????

With dual core one cpu emulate a PPC at full speed, one cpu emulate gfx and disk and the performance is slowest than quad core.