The Sinclair QL Forum

Could this Be The Fastest QL Ever

Hi,

How fast is the PC?

simon629 wrote: Thu Aug 07, 2025 7:59 am Could this Be The Fastest QL Ever

Due to the GIT compiler based 68K emulation, WinUAE running QDOS Classic is likely to score higher with QTOP-Index, at least for the CPU related parts.

My low-end PC from 2019 with QDOS Classic under UAE:

Peter wrote: Sun Aug 10, 2025 12:03 pm My low-end PC from 2019 with QDOS Classic under UAE:
qdos_uae.jpg

Thats a pretty hefty "low-end" PC youve got there! Nearly 3x faster than QPC2 on my 8 year old i5 PC and 5x faster than the same PC running Qemulator with Qdos or Minerva at full speed. Either UAE is very good, or your PC is very fast or theres some other magic going on..

pjw wrote: Sun Aug 10, 2025 12:46 pm

Peter wrote: Sun Aug 10, 2025 12:03 pm My low-end PC from 2019 with QDOS Classic under UAE:
qdos_uae.jpg

Thats a pretty hefty "low-end" PC youve got there! Nearly 3x faster than QPC2 on my 8 year old i5 PC and 5x faster than the same PC running Qemulator with Qdos or Minerva at full speed. Either UAE is very good, or your PC is very fast or theres some other magic going on..

UAE is in fact very fast as it uses more than one CPU core to pre-compile 68k code into x86 code in parallel with running the actual 68k emulation. I don't think QPC2 is actually using more than one CPU core.

tofro wrote: Sun Aug 10, 2025 4:10 pm UAE is in fact very fast as it uses more than one CPU core to pre-compile 68k code into x86 code in parallel with running the actual 68k emulation. I don't think QPC2 is actually using more than one CPU core.

I think the massive speed advantage mostly comes from the JIT compiler, only to a lesser degree from the multicore support.
Is there any QL emulator with JIT compiler at all? I only have vague memories that Daniele was experimenting with it.

By the way, Mark has implemented QDOS Classic for Amiga in a cool "bare metal" fashion. He replaces the Amiga boot ROM for UAE, so no Amiga OS or software is involved at all. The emulated system immediately boots as a QDOS machine.

Is there any QL emulator with JIT compiler at all?

I did look at it, but incorporating the UAE JIT is not a simple task as its quite tightly coupled to UAE!

Peter wrote: Sun Aug 10, 2025 12:03 pm My low-end PC from 2019 with QDOS Classic under UAE:

Could you share some specs on your low-end PC?

Peter wrote: Sun Aug 10, 2025 9:36 pm Is there any QL emulator with JIT compiler at all? I only have vague memories that Daniele was experimenting with it.

Yes, in 2001-2002 I wrote a prototype version of Q-emuLator that compiled basic blocks of 68K code to x86. I only made it available for a short time and dropped it since it was not compatible with some self-modifying QL programs. Interpreters are also already pretty fast on modern PCs.
Last year I took another look at it, but noticed that QLE doesn't even start anymore on it, probably because it runs a number of Q-Liberated programs and Q-Liberator seems to produce some self-modifying code.