A Question of Win98Kernel

See subj.

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What is the difference in kernel between 9x and NT, by start?
What does it mean - the programs running in the shared space? They are running in one virt.machine or use Big real(unreal mode) ?

Thanx!

PS.
(i know how NTkernel works)

Hey, I don´t belive that nobody knows!

Everybody said that NT has no DOS inside and do not know how 98 starts?!

Are you referring to program behavior, ie NTVDM operation? If so, then the Windows 98 environment does run in a shared program space, where the NT based OS can use separate(non shared) program space to run 16bit applications. Shared memory indicating that the programs are not in isolated memory blocks and the crash of one application may adversely impact other programs.

Xaotic said:

... Windows 98 environment does run in a shared program space, where the NT based OS can use separate(non shared) program space to run 16bit applications. Shared memory indicating that the programs are not in isolated memory blocks and the crash of one application may adversely impact other programs.

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Meana-one virtual 86 for all 16bit progs?? Thanks, but why is ´w98´ unstable when, for exmpl. doom2 crashes and I Ctrl-alt-del it?
The other ? is : win98 is mostly16bit??(see difference between system and system32 dirs under xp and 98)

Vovan said:

Meana-one virtual 86 for all 16bit progs?? Thanks, but why is ´w98´ unstable when, for exmpl. doom2 crashes and I Ctrl-alt-del it?

Click to expand...

When u ctrl-alt-del, system resources are not relinquished. One possibility...

Since it's a shared memory space. the "crash," even if a hang and termination through CRTL+ALT+DEL, can change values in nearby registers, thus causing other program and system faults. With separate memory spaces, programs run in reserved memory spaces and there is less danger of data being shuffled inadvertently and causing problems.

Yes, Win98 is largely a 16bit OS that can run 32bit applications. True 32 bit OS started with the NT based kernels.

Xaotic said:

Since it's a shared memory space. the "crash," even if a hang and termination through CRTL+ALT+DEL, can change values in nearby registers, thus causing other program and system faults

Click to expand...

Does it mean that win98 uses one registry context for all progs at 16bit?But it´s not possible... That won´t enable the task switching, since a lot of contexts are running under one virtmachine. For exmpl : i have doom1 and doom2 running under w98 and when d1 crashes windows can still load the registy context of doom2 (ip,...), although dooms have a boot loaders that organize a big mode for ´em(DOS4GW). How does this function at all under one virt 86??? I think win98 makes two virt 86 for every task .. or?
ANY IDEAS???

Is that shared space one virtual 86? or its a big mode?

Since W98 is not true multitasking(it's sequentially threaded), it can actually be considered as one virtual machine. There are a variety of threads running at any given time for the different processes and applications. These alternate for priority with the processor. In the case of DOS4GW, and many others, these will be separate multithreaded instances of the same application, but still running as sequential threads in a shared memory space. By considering each task as a process with associated threads, it may be a bit clearer. The threads are associated with specific tasks and once processed the data is returned to the specific memory addresses associated with that task. Instability can result when bad commands or data cause the returned data to either be misassociated or written wrong registers. Another root of some of the instability with 98, is that the OS is actually running in the shared memory space as well.

everyone everyone, just think for a moment. Windows 98 is crap = crashing = very unstable = upgrade to a better OS

some of my old pcs p100 and the like run win98 se max run time now at 3 weeks (got no phone line to get work for home so they are off and im on at uni)

Xaotic said:

Since W98 is not true multitasking(it's sequentially threaded), it can actually be considered as one virtual machine. There are a variety of threads running at any given time for the different processes and applications. These alternate for priority with the processor. In the case of DOS4GW, and many others, these will be separate multithreaded instances of the same application, but still running as sequential threads in a shared memory space

Click to expand...

But does this say that w98 is a MULTITHREADING OS? How it is possible? Do you think - software organisation?

UnderTaker-CS said:

everyone everyone, just think for a moment. Windows 98 is crap = crashing = very unstable = upgrade to a better OS

Click to expand...

What we are talkin´ ´bout is not the upgrade. I wanna only know the structure of w98 without microsoft´s silly doctrine. NTs are brightly covered im many non-microsoft books.

Yes, multithreading is probably the best description of its function. In terms of architecture, it's a step between W3.x, where the processing was an extension of single tasking DOS mode, and NT, which with support for multiple processors, is a true multitasking environment. The threads are queued by priority for processor time, though without the granular control in NT OS. Software is definitely the controlling value, in this case the kernel itself sets the priorities. Another way to think of it might be the WOW controlling a single NTVDM, with all applications running within it's context.

Xaotic said:

Yes, multithreading is probably the best description of its function. In terms of architecture, it's a step between W3.x, where the processing was an extension of single tasking DOS mode, and NT, which with support for multiple processors, is a true multitasking environment. The threads are queued by priority for processor time, though without the granular control in NT OS. Software is definitely the controlling value, in this case the kernel itself sets the priorities. Another way to think of it might be the WOW controlling a single NTVDM, with all applications running within it's context.

Click to expand...

..WOW..?? what does it mean?

What I know for sure is : NTs priority and processor time quants for every task are defined seperately . Because any prog can initiate a I/O during operation.