Multitasking in different Oses

[chavalin]

Hi everybody,

I've always heard that there are two types of multitasking: the "real" ONE which is pre-emptive multitasking implemented in Windows NT/2K/XP, Linux, Mac Os X and an emulation (is there any name for it?) used in Windows 95/98/ME.

Is that true?

Also I've heard that the "real" multitasking wasn't implemented in MAC OS till MAC OS 9 is that true?

And also what determines whether one OS has "real" multitasking or not? The planificatión scheme?

Another unrelated question I've got is: What's the stability in MAC OS 7/8/9 (I suppose in MAC OS X it's obviously unix grade stability)?
How that compares to WIndows NT/2k/XP?

I've used MAC OS 8.6 and it's stability was very very poor at a much lower grade than Windows NT an much much worse than W2k.

Thanks very much.

 

[NogginBoink]

There's preemptive multitasking and cooperative multitasking.

In Windows 3.1 and earlier, it was all cooperative multitasking. Each app is supposed to give up control of the computer so that they can all share.

Under NT, it's all preemptive, where the OS steps in and says to the app, "you WILL give up the processor now."

I think that win32 apps are preemptive but 16 bit apps are cooperative under Win9x.

 

[n0cmonkey]

<< Also I've heard that the "real" multitasking wasn't implemented in MAC OS till MAC OS 9 is that true? >>



Mac OS 9, to my knowledge, did little or no multi-tasking. I dont think I can open 2 real applications at once in it.



<< Another unrelated question I've got is: What's the stability in MAC OS 7/8/9 >>



Not very good.



<< (I suppose in MAC OS X it's obviously unix grade stability)? >>



Mac OS X is much better.



<< How that compares to WIndows NT/2k/XP? >>



OS 9 (the only one I have experience pre-10) does not compare to a well administered Win2k machine on *GOOD* hardware. Good meaning no cheap VIA mobos or anything

 

[spamsk8r]

hey n0c, my via mobo runs 100% stable in win2k, dont bag on them, i really think the kt266as and the new kt333s are finally getting to be very stable

 

[n0cmonkey]

<< hey n0c, my via mobo runs 100% stable in win2k, dont bag on them, i really think the kt266as and the new kt333s are finally getting to be very stable >>



Well my VIA whatever the hell it is sucks. Ill take Intel/AMD/Server works any day.

 

[chavalin]

<< In Windows 3.1 and earlier, it was all cooperative multitasking. Each app is supposed to give up control of the computer so that they can all share. Under NT, it's all preemptive, where the OS steps in and says to the app, "you WILL give up the processor now." >>



So it's just as I thought it was, It's the OS scheduler (I supose it's called the same as in cpus) and it's capability that determines the way multitasking behaves. In cooperative multitasking the scheduler must be following some sort of FIFO algoritm and in preemptive multitasking it should be something like a Round Robin.



<<
<Also I've heard that the "real" multitasking wasn't implemented in MAC OS till MAC OS 9 is that true? >
Mac OS 9, to my knowledge, did little or no multi-tasking. I dont think I can open 2 real applications at once in it.

< Another unrelated question I've got is: What's the stability in MAC OS 7/8/9 >
Not very good.

< (I suppose in MAC OS X it's obviously unix grade stability)? >
Mac OS X is much better.

< How that compares to WIndows NT/2k/XP? >
OS 9 (the only one I have experience pre-10) does not compare to a well administered Win2k machine >>



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