I want control of my machine DAMNIT!!!
 

I am completely fed up with a multitasking/multiuser Linux platform that in its utter stupidity is able to let the user loose control completely.
I have SuSE10.0 and when I use a CPU and/or disc intensive process (like MainActor for video rendering), that proces takes over the machine completely!
So when I want to renice that process, even the renice command itself is not available anymore. I can type in "man renice" to get the syntax right but after that I might as well make myself a cup of coffee and drink it and after I have drunk it, I might go back to the machine and perhaps it has already come up with the manual.

How in heavens name is it possible that an ordinary process like video rendering is able to get such privilige that it can overpower the whole machine, while someone at the keyboard who is trying to get access to the machine is completely ignored!

I always thought that a multitasking/multiuser system somehow is clever enough to realise that when someone is typing something at the keyboard, that person should not be kept waiting for minutes and minutes without the machine noticing his presence.
I can type Ctrl-Alt-F1 to go to another console but also there, while trying to log in, I am completely ignored! I am timed out! GOD DAMNIT!!!!

What if the superuser is desperately trying to get access to the machine for any emergency and the machine tells him that he is not important because the video rendering of MainActor has ALL priority? Na na nana na!

try:

Or maybe, it's not your system, and not linux at all. Maybe, just maybe, its MAIN ACTOR. Multi-tasking works great in linux. I've never had any program freeze up my system, even when I'm renering a dvd from my digital camcorder.
In other words... STOP YOUR COMPLAINING AND DON'T USE WHAT YOU DON'T LIKE

The Linux kernel is (by default) optimized for throughput, not for response time to keyboard/mouse events. If you have a cpu/disk intensive process, the kernel will favor that process. If you want a kernel that is more responsive to user events, compile a fully preemptible kernel.

I'm not sure what the default kernel on SuSE has enabled, but you can tell if your kernel is preemptible by running uname -a. A preemptible kernel is indicated with the word PREEMPT. For example, here's the output on my system:
Under Linux, a process can alter its scheduling (depending on its privileges). Some audio/video applications will grab realtime scheduling if possible. If MainActor is doing this or something similar, it will have much higher priority over other applications.

I have never had problems similar to what you are experiencing. Response is downright snappy on my Linux computers.

Also, what are the specs of your PC in terms of the CPU and RAM?

when your machine starts slowing down open a terminal window and type $ top - confirm first that the video program is definately the process using up all the resources. Also check your RAM usage and disk utilisation..

I assume you have a pretty powerful machine with lots of RAM and fast Hard Disk etc if your doing the video work... how Much RAM do you have and also how big is your swapspace ?

The response to the uname -r command is:

Linux GorisPC 2.6.13-15.11-default #1 Mon Jul 17 09:43:01 UTC 2006 i686 athlon i386 GNU/Linux

I have a 512Mb machine with AMD Athlon XP 1800+ processor.

im no expert in video edditing but i think thats "chicken shit". ofcourse that depends on the parameters of the file so excuse me if its something small ur rendering.

Also, my kernel is setup with "CFQ" (completely fair queue) scheduling, this sped up the response of other programs while a major cpu drain is in progress.
The two other schedulers availble are "Anticipatory" and "Deadline". See "Block Layer -> IO Schedulers" section when configuring your kernel.

What suprises me is that when the machine is started, the physical RAM use is already 450Mb, leaving about 60Mb free for other applications to start. But things vary. Three days ago, when using kino to render a movie (in my first post MainActor was mentioned but I meant kino) the whole of the physical RAM was used (only a few megabyte were left free), while half the swap space was used, being about 250Mb of 512Mb. This evening, under what I expected to be the same circumstances), no swap space is demanded at all (though once again the physical RAM is used nearly comletely, only a few megabyte free) and the response of the machine was a bit sluggish while kino was rendering. Kino was using about 95% of the CPU and hardly any RAM. When renicing the program, the machine became very responsive.
I think I will give new information when things are getting as bad as they did a few days ago, when the machine was nearly unusable.

When you start your machine, and the memory usage is this high (I'm assuming you're not counting memory used for cache), run top and sort the display relative to memory usage (it's sorted by the %CPU column by default, use the < and > keys to move the sorting column left or right respectively; on my system, pressing > once is enough to sort by %MEM since it is directly adjacent and to the right of the %CPU column).

The will show what process (if any) is hogging your memory.

By the way, the original symptom reported by your first post now sounds more like your computer was "thrashing" - using so much swap that the head of your disk drive had to seek back and forth for virtually every memory read, slowing down disk access time. Because disk activity is slow, and every process is waiting for disk I/O time rather than CPU time, your system will REALLY slow down. This only happens when your computer is under incredibly high load (load beyond your computer's capability).