Re: Unix vs NT

I am not really tight on this yet ( still learning about NT ) but my understanding is that NT does strict time slices: after about 7.825 ms, any thread is forced to sleep so that another thread at the same or higher priority can run. (Making obvious changes for multiprocessor machines). This "quantum" time slice is fixed by CPU architecture, alpha is a bit shorter slice than x86, etc.

Having said that, Unix is not as strict with its time sharing. I wish I could look this up right now, but think that switches occur naturally and asynchronously: based on context switches, i.o waits, resource sleeps, interrupts, etc. rather than the goosestepping 7.825 ms of the NT thread time slice.

I'm not an OS designer, neither am I an expert on application design , but i do find that most any flavor of unix will kill most any flavor of NT on a given chip, but then again, Unix has this 20-odd year advantage ( and it doesn't have to run all the embedded crap that NT offers ) at tuning and configuring, and it's whole "mindset" is different: "many small tools" rather than "Everything in the OS".

Short story is: time *is* sliced, but the processor scheduling algorithms are different.

John wrote in message <37246F3F.43302025_at_spam.com>...
>I'm curious, how does Unix do the multitasking if it isn't using a
>"time-slicing" method?
>
>Allan Kelly wrote:
>
>> Unix (including Linux) is a "true" multitasking, multiprocessing
operating
>> system, Windows NT runs multiple processes using a "time-slicing" scheme
>> that really stinks. If performance is an issue, go with Unix, if price is
an
>> issue go with NT
>>
>> Allan Kelly
>>
>> Frans Trip wrote in message <37205E2B.C36DEDDD_at_tref.nl>...
>> >Why Oracle on Unix ? (Digital Unix 4.0 E)
>> >Why Oracle on NT ? (4.0 US sp3)
>> >
>> >Oracle to run = 7.3.4.
>> >
>> >Please tell me the pro's and con's
>> >
>> >Reply to newsgroup or tripf_at_vertis.nl
>> >
>> >
>
Received on Mon Apr 26 1999 - 20:45:28 CDT