[litwr]

I've just finished my emotional article about processors - https://litwr.livejournal.com/3096.html

Originally Posted by Don_Adan

Every 68k Amiga code stored fully in chip or fast memory can be fully relocatable.

I can only repeat that you can't make relocatable an instruction with two indices, for example,

MOV table(A0,D1),D2

The idea of 100% relocatable code for 68k or PDP-11 is a kind of chimeric one. You can do it on the purpose but generally it is bigger and slower. Thus above 99.9999% of 68k programs do not consist of 100% relocatable code. But 8086 gives you an opportunity to use 100% relocatable code just limiting us with its size: we have to use less than 64 KB for codes, 64 KB for data, 64 KB for a bit slower extra data and 64KB for stack. With 80386 you can expand 64 KB up to 4 GB and get two additional segments for extra data but this is not supported by DOS directly. However 80386 can give 100% relocatability with built-in MMU too. So COM-format is the demonstration of x86 ISA superiority. It should be absolutely clear now.

Originally Posted by roondar

Don't be silly now, litwr clearly never accepts anything that supports the 68000 as being as good or better than 8086 as he has determined that any such information is clearly biased nonsense. Obviously, only articles that detract from the 68000 and praise Intel are accurate and the rest should be ignored

Thank you for sharing you opinion but it is not true.

Originally Posted by roondar

A couple of things about your list:
1) you forgot to mention the 68040 result, which is significantly higher than the 80486 result. It scores 21 MIPS in your list (see manufacturer Motorola).

3) the 486 result seems really low, I have seen claims of 20 MIPS@25MHz elsewhere. Which would make some sense as this chip was seen to be competitive with the 68040 and that clearly wouldn't have been the case if it ran upwards of 30% slower.

However, it doesn't really matter anyway, as the claim that the 12MHz ARM2 was competitive with a 25MHz 486 is still plainly false.

They show the ARM2@12MHz is at best 45% of the speed of a 25MHz 486. Or, perhaps easier to grasp, the 486 is at least 2x the speed of the ARM2.

Calling that difference 'a bit slower' is disingenuous at best.

They also show that the ARM2@12MHz is slower than both the 386@33MHz and the 68030@33MHz (let alone one at 50Mhz). Which conforms exactly to what I stated at the start of our little exchange about the ARM2.

The article you linked through also supports my position and not yours as it claims that the ARM2@8MHz challenges, but does not always beat, a 16MHz 386 at integer tasks. And loses at floating point heavy tasks & sorting. Extrapolating that to a 33MHz 386 and a 12MHz ARM2 would give you a 50% bonus for the ARM, but a 100% bonus for the 386 => the 33MHz 386 should be faster and that is exactly what we already knew from the tables above.

Even if you look at the rather impressive Dhrystone results of the ARM2@8 vs the 386@16, scaling these up to 12 and 33 MHZ still has the ARM2 lose.

In other words, the evidence you managed to find does not support any of your claims and in fact supports everything I've said, but you're going to continue claiming your earlier opinions are probably correct anyway. Got ya.

Sorry I really knows little about 68040. I know only that it was not used so widely as 80486, it had lower frequencies, problem with FP, ... I can add that it was used surprizingly rarely and was eventually replaced by PowerPC. So it showed some very serious shortcomings that prevented its success. Maybe it was also too costly. In the list 68040@25MHz shows about 17.5 MIPS on average, 80486@25MHz gives slightly more but the difference is rather insignificant.

I have only claimed that ARM@25MHz can be faster that 80486@25MHz.

Indeed, the official benchmark shows that 80386@33MHz is faster that ARM@12MHz. However they sometimes used Acorn's Basic against C-compilers at x86! My experience with ARM let me say that ARM allows to write very compact and fast codes which are much better than codes generated by compilers of the 80s or even 90s.

Originally Posted by roondar

And seriously, approximate cycle counts for an untested bit of code? What use are those exactly (I mean, exact cycle counts might be useful, but approximate seems rather useless)? And what exactly does one tiny algorithm prove? (answer: nothing, really! It might be an outlier and considering other benchmarks disagree with these results, it is actually likely that it is an outlier)

Why do you call line drawing code untested? It is fully tested for x86, 68k and ARM. I have made very accurate cycle counting, anybody may check it. The code is rather short it will take only less than 10-15 minutes. I said "on average" because the codes have conditional instructions which timings depend on condition. I took 50-50 in those cases.

Originally Posted by roondar

And all of this is without accounting for the fact we're comparing the wrong CPU's. As I researched (ok, Googled ) this post, I found the 1991 Archimedes at GBP999 was not running a 12MHz ARM2. It was in fact the A5000 running a 25MHz ARM3*. Which indeed gets a lot closer to the 486/68040 running at the same speed, although the ARM3 MIPS rating is still clearly lower than either of these two.

However, the given price of the A5000 did not include a hard disk or monitor, where the 486 I quoted did have a monitor and hard disk. As such, I'm still not convinced about the price/performance ratio being in the Acorns favour.

*) The 12MHz variation seems to be the A3010, which was released in 1992 for GBP499. There may in fact be other 12MHz variants prior to 1991, but the information on what is actually in the the various Archimedes models is somewhat scarce. However, even if they did exist, all potential candidates prior to 1991 were a lot more expensive than the GBP999 A5000.

IMHO the UK computer market was stormed by NA companies. Commodore sold 2-3 times more Amigas in the UK than in the gigantic NA market. Olivetti provided poor management and refused to use their trade net to sell Archimedes. And there was IBM PC factor too. So Acorn did rather very well and produced very good computers in those circumstances. I met an Archimedes with 8MHz ARM-2 in 1991, I was very impressed by its performance. It was more 10 times faster than my Amiga 500. Indeed sound and graphics of A500 was approximately at the same level.