English Amiga Board - View Single Post - What was wrong with the Amiga 1000/500/2000?

litwr · 24 January 2021, 13:43

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Originally Posted by roondar

Fast RAM for the A500 exists in two forms: "fake" Fast RAM (the cards you put in the trap door slot, also called Slow RAM) and "true" Fast RAM, which is connected to the side slot.

Generally the increase in performance for having true Fast RAM on a 68000 based Amiga is around 10-15%. This increases for faster CPU's.
What I mean is that executables can exit with any return code between -2 billion and +2 billion (IIRC anyway, you get to return a signed long word). It's possible the IF statement doesn't support all of them, but to be honest I don't usually make scripts so I can't verify that.
There is a way to kill tasks on OS 2.0+ (in fact, Exec has a built-in function for it in ROM), but you're correct that it's probably not included as a standard command. I'm 100% certain I have a killtask or some similar command somewhere form the developer CD though, so it is actually possible.

Just use the correct 'nice' statement on Unix. I forget which value to use, but you can hang the entire system like that. Same with Windows all the way up to Windows 10, if you select the correct process and give it high enough priority you can quite easily hang the system.

Anyway, I don't really agree with this to begin with. The scheduler works fine if you use it as instructed. The instructions for changing task priority tell you that you shouldn't increase priorities that high. If you do so anyway, purposefully disregarding how the system works, then that's not the schedulers fault.

Thank you very much for your clarificatons about Fast RAM cards for the Amiga 500. However my misconception about fast RAM for the Amiga 500 has several excuses. All this matter is still rather in dense shadow. Is it a part of something known as the "Commodore curse"?

The fast RAM cards for the Amiga 500 were very rare and expensive. It is sad that even http://amiga.resource.cx/performance.html doesn't have data for such cards.

I can actually activate Fast RAM only after I ran FastMemFirst system utility. There is no such program for the A1200 which activates its fast RAM automatically. The results are here. So I can note that Fast RAM for the Amiga 500 provides only about 2% speed boost - it is rather funny.

But you are definetely wrong about return codes. They can have any values but you can use only five of them. It is, indeed, really crazy. IMHO it was a strange Commodore manager who forced engineers to cannibalize normal usage of return codes.

The possibility to kill a process is definitely a part of the proper preemtive multitasking because such kind of multitasking assumes that the system can control its processes. It is well known that TripOS, which was used as a base for Workbench, has a serious flaw - it lacks resource tracking, and this maybe caused a problem with the process kill.

It is sad that you don't want to help people to get a more complete list of the first Amigas drawbacks. It is quite natural for a scientific approach to systematize things.

I have never read a complaint that the nice utility can crash a system. For example, nobody mentions `nice' here - https://unix.stackexchange.com/quest...single-command
The use of `nice' can cause problems - https://www.linuxquestions.org/quest...Wa84FE4E9J8EwQ - but is not the system crash. However you are rather right. But you can't set too high priorities in Unix as a user, it requires rights of superuser.

So in Amiga OS, it would be better to use a bit different "mechanics" for working with the priority.

Quote:

Originally Posted by roondar

You also forgot the counter is down to either 9, 8 or 7 depending on which of my answers you actually intend to take into account

Of course, your answers have made my claims #4 and #10 less valuable. Thank you again. But in new less valuable forms they still exist.

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