[Info-vax] nice for VMS

[Michael Moroney]

"Fred Zwarts" <F.Zwarts at KVI.nl> writes:


>>>    What's wrong with "set process/priority=1"?
>> 
>> Priority zero is better because then it just scavenges CPU time.

>Are priority 0 processes still competing with the NULL process,
>or do I carry to much of the VMS history with me?
>(I know the NULL process is no longer visible in newer VMS versions.)

I believe the null loop is actually a loop in the executive looking for
processes to run, so I think it's more than the "NULL process not visible".

I suppose you could run an experiment:  On an otherwise totally idle
VMS system (single processor for simplicity), run a CPU-bound process
at priority 0 for a fixed length of time (say 1 minute) and see how much 
CPU time it uses.  ~1 minute CPU time = no competition.  30 seconds =
split evenly with "something else".  Might be interesting to do the same
on an old version of VMS with a visible NULL process to see if they
really do compete equally.