[RC5] WinNT Priority

Dysart, Derek DYSD1 at Aerial1.com
Wed Jan 7 14:22:50 EST 1998

> On Wed, 07 Jan 98 14:15:15 +0100, Morten Torstensen wrote:
> >NT has 16 different priorities and no classes like OS/2. At least
> that's 
> >what the instructor told me on the MS admin course. This rough
> schedueling 
> >is generally divided in four named priorities, low, normal, high and 
> >server(?)
> i beleive that top ones called real time (sound just like os/2s time
> critical to me...)
> > at something like pri 4,7,12,15 (from my memory, it might not be 
> >completely accurate).
> >
> >In OS/2 you have idle, normal, high, and time critical with deltas
> within 
> >them from -31 to 32.
> Ok what i really want to know is this: In OS/2 i can type 'pstat' and
> see the exact priority every process and thread is running at. Is
> there
> an NT equivalent?
> ----------------
> daniel carter 
> 1 crown st, dunedin, new zealand ;-} 
> I'll never forget the 1st time I ran Windows, but I'm trying..
There are several utilities in the Windows NT Resource Kit CD that allow
you to view process priority and the individual thread priorities within
those processes (I'd send them to ya, but I don't know if they are
Copyrighted).  It probably is not too necessary, however.  The following
is an excerpt from the resource kit:

The base priority class of a process establishes a range within which
the base priority of the process can vary. Processes are assigned to one
of the four base priority classes, (Idle, Normal, High, and Real-time).
The base priority class is set in application code and is not changed by
the operating system [Ed: except, of course via Task Manager, et al].


Dynamic priority boost. When a thread has been waiting for a resource or
for an I/O operation to complete, Windows NT boosts its priority as soon
as the thread becomes ready. The amount of the boost depends upon what
the thread was waiting for, but it is usually enough to assure that the
thread runs soon thereafter, if not immediately. For example, the
dynamic priority of thread waiting for disk I/O is increased by 1 when
the disk I/O is complete. The dynamic priority of a thread waiting for
keyboard input is increased by 5 when it is ready.

The way I read this, your backup application should be fine since it is
very I/O intensive.  Since rc564 is not very I/O intensive, it most
likely will not get boosted, save during block transfer operations
(fetch/flush from buffer/keyserver).

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