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DISGUISED
12-12-2001, 11:46 AM
I hear the term Multitasking used often in relation to windows. Is this a "True" multitasking OS. With the use of a swap file I don't see how it could be. Am I correct? I am trying to solve a little dispute with some buddies of mine. Can the same be said about Linux? UNIX?

maes
12-12-2001, 11:57 AM
I don't really know. But I think true multitasking can only be done if you have 2 processors. Now he only divides the time between the different tasks. You arenít doing them simultaneously

adrianxw
12-12-2001, 12:14 PM
So define "True" multitasking. On any single processor system, regardless of it's OS, only one thread of one task is actually running.

DISGUISED
12-12-2001, 04:00 PM
I understand what adrianxw is saying but I have a friend who keeps telling me otherwise about UNIX. He says that UNIX has the only true Multitasking ability because it can tell a processor to do one task in the foreground and another in the background simultaneously. I am a confused about what he means or if he actually knows what he is talking about at all.

Nick
12-12-2001, 04:55 PM
True multitasking as opposed to cooperative multitasking .

/dev/null
12-12-2001, 05:21 PM
Using two processors is called multi threading.

Unix/Linux users have been multitasking for decades! (microsoft claims to have true multitasking but that depends on your defenition...)

hehhee i just had to post this

Q: Does Windows offer true multitasking?
A: Yes. It's called Interactive Multitasking, meaning you can go work on other tasks while waiting for your computer to reboot each time Windoze crashes.

lightatdawn
12-12-2001, 06:11 PM
Technical Microsoft definition: ;)

Threaded Multi-Tasking:
The cooperative multi-tasking found in Windows 3.1 has now been
replaced with the far more powerful "uncooperative multi-tasking".
This enhancement will allow several processes to crash
simultaneously. Our new crash protection facility greatly enhances
the multi-tasking environment. Should one process fail, the CPF will
prevent this process from being disturbed by other cleanly running
processes. The multi-threading environment allows one process to
generate multiple errors, while still remaining separate from other
threads.

Yoshi
12-12-2001, 07:17 PM
It is called "Jumpy Tasking" because it load a little bit of one thing, and then another. So it is ssssssssloowwwwwwwwww.
------------------------------
Engineer223

Betazep
12-12-2001, 08:23 PM
Unix does multi-task...

and your friend is right on that part.

There are a number of PIDs (process IDs) that can be running at the same time in the forground and background.

Hate to burst his bubble though... but Windows can do it pretty much the same. (DOS cannot)

Ever run Norton antivirus (or equiv) while searching the internet and/or playing a game. It will run in the background. Although, you will see serious performance decreases that are not necessarily due to ram.

I think that there are more technical reasons why some say Unix is 'true' multitasking and Windows isn't. But if the end result is transparent to the user, does it really matter.

In the right hands, Unix is very powerful... but then again I have seen some pretty powerful DOS junkies as well.

Not a very definitive answer for me... but I am beat tired...

/dev/null
12-12-2001, 08:49 PM
Yes, you can "Truly multi-task" in DOS, but you have to use the very clever and very scary "PT-DOS".

Nick
12-12-2001, 10:26 PM
I think also to be true multitasking the operating must also
keep processes from stepping on each other. So windows 98
isn't even know it supposivly keeps process from writting over kernel memory. Still not sure though.

Unix is multi-user but windows isn't really designed to be.

Scourfish
12-12-2001, 10:52 PM
You wanna talk about true multitasking? True multitasking is when I am at work at the old supermarket and I am able to finish bagging somebody's order and half assedly tell them to have a nice day at the same time.

adrianxw
12-13-2001, 04:10 AM
>>>
He says that UNIX has the only true Multitasking ability because it can tell a processor to do one task in the foreground and another in the background simultaneously.
<<<

For the reason I gave before, this is simply not true. It may appear that a single chip is running n foreground tasks and another n background tasks, (Unix, Windows and a great many other OS's do this), but a single CPU can only process one thread at a time, the OS divides chip time between the running tasks.

I believe your friend does not understand what he/she is talking about, and is simply talking up Unix.

>>> why some say Unix is 'true' multitasking and Windows isn't.

It is because the Unix lobby don't like the idea that anyone else can "do" what they can do, so they obscure the definition to make sure nobody bothers to check. Simple fact, there were multitasking operating systems around before Unix - they hate that!

/dev/null
12-13-2001, 08:31 AM
"It is because the Unix lobby don't like the idea that anyone else can "do" what they can do."

welll aparently you sound like a winders fanatics... migh i remind you that mircosoft.com and hotmail.com run unix? ironic isnt it...

Justin†W
12-13-2001, 10:24 AM
*sniffle* I remember the Amiga. True multitasking, super computers. Several processors, never crashed, could do high quality video editing in 1987 for less than the price of a 486. Even the floppy disks never went bad (still have some that are perfectly good!!?!)

Anyway, both newer versions of Windows and pretty much all versions of *nix are capable of running on multiprocessor systems, though neither of them have yet to do it particularly well do to *nix terrible design and Windows copying them.

Some might also argue that multiple pipelines into the processor (which work like an assembly line) allows for a sort of multitasking.. but that is processor design and has nothing to do with the OS.

-Justin

adrianxw
12-13-2001, 10:28 AM
>>> welll aparently you sound like a winders fanatics...

Actually I'm not, I am not a fanatical supporter of any OS! What I do see though, is an awful lot of *nix people slagging MS off for quite unjustified reasons. This thread is a typical example. Unix CAN do this and is the ONLY OS that can do this - this is straightforward propoganda, and is completely incorrect. I hear this more often from *nix camps then any other, hence I react against it. I have used Unix as well, and like it. The OS is not the salient factor here it is the devotees.

>>> migh i remind you that mircosoft.com and hotmail.com run unix? ironic isnt it...

Why?


Actually, I can remember Hotmail being brought down a number of times...