Something alluded to, but not really elaborated on, is what the motivation is for <i>emulating</i> progressively newer CPUs, versus virtualizing them.<p>With old hardware, the sort I imagine 86Box is mainly used to emulate (it's how I use it, anyway), old OSes rely on specific behavior of old systems and peripherals that can't be easily virtualized through KVM + QEMU or the like. A mixture of processors being too fast and behaving subtly different, possibly due to differences in "undefined behavior".<p>I doubt there's a binary cutoff point where it's obviously more useful to virtualize or emulate, but it's obvious that emulating an 80386 is ideal, and virtualizing a "Core 2 Duo" is ideal, for running software from those respective periods. Is the Pentium III desirable to emulate, and simply not computationally feasible, or is this just people wanting to make cool things for cool things' sakes? Or a little of both?
It’s probably not even possible to emulate the Pentium Pro (or any other out-of-order x86 CPU) in a cycle-accurate fashion at the original speeds on contemporary hardware. Just attempting to match the original behavior for instruction scheduling, cache models, branch prediction, etc. would blow your CPU budget.
Sorry but not getting to point of cycle-accurate emulation of recent x86 CPUs. What could possibly benefit ? The performance is going to be a disaster compared to say qemu....
Here's the discussion from reddit. It appears as though the developer is loudly promising PIII emulation but has a history of not delivering.<p>I would guess this article is an effort to distance themselves from this dev if people google it<p><a href="https://www.reddit.com/r/emulation/comments/tjnxg3/why_not_pentium_iii_86box/" rel="nofollow">https://www.reddit.com/r/emulation/comments/tjnxg3/why_not_p...</a>
They need to stop adding features and start completing features. Get accurate instruction cycle counts for all the CPUs up to and including the Pentium Pro. Be more clear on what is happening when you disable cache in the bios for platforms that allow this. Just saying that it reverts back to interpreter mode seems false. It allows me to run very fast clock CPUs with no slowdown. It's doing something different than just disabling the dynrec. I still just use PCem every day instead though. I trust that code way more than 86box mainly because of the machine window with the history graph and seemingly way more reproducible behavior in terms of performance. 86box is so wonky.<p>Socket 8 Pentium pro 200 is just universally great for everything. Disable cache and move down to 150 and you can run older stuff quite well with no hyper speed. I have a bunch of old system presets I use every day. I got a win98se setup that is usually socket 7, super 7 or socket 8 for most stuff. It has 4 55GB VHD drives mounted to it. It's great. Every DOS game is just there. Bunch of Windows software ISOs too. Got a bunch of 2gb dos compatible disks and every DOS version installed and ready to go. I'll toy around with all the OS/2s sometimes too, very cool system.<p>But please, just polish what is there!
Article claims it’s not possible to emulate a Pentium III at full speed on an Apple M1, and so there’s no point to a fork attempting this feat. But isn’t that exactly what Rosetta 2 does?
Arguably, cycle-accurate emulation should be done with FPGA support anyway. The Pentium III is old enough that there should be no legal obstacle to implementing new compatible hardware.
Completely OT, but switching to a Firefox tab with TFA loaded takes noticeably longer than switching to other tabs (about 3 seconds vs less than a second).
I don't understand,the yuzu (switch) emulator has excellent performance and correctness. It perfectly emulate a modern ARM cpus at multiple GHz and properly emulate the Tegra Nvidia GPU.<p>Why would emulating x86 be <i>so much</i> harder, especially since you can actually use the host x86 cpu... via hardware hyoervisors e.g.
<a href="https://github.com/intel/haxm" rel="nofollow">https://github.com/intel/haxm</a>