Re: Linux Kernel Patch; setpriority

[Bill Davidsen]

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  Rather than expect people who have been following this to reread I'll
put this here. I believe the capability of nice(2) setting and restoring
is (a) very seldom useful given the new scheduler, and (b) can be done
with a bit of effort and no assult on SUS by doing the nice work in a nice
thread. 

  Code is attached.

On Wed, 27 Mar 2002, Chris Wright wrote:

> * Stephen Baker ([e-mail]) wrote:
> > 
> > This patch will allow a process or thread to changes it's priority 
> > dynamically based on it's capabilities.  In our case we wanted to use 
> > threads with Linux.  To have true priorities we need root to use 
> > SCHED_FIFO or SCHED_RR; in many case root access is not allowed but we 
> > still wanted priorities.  So we started using setpriority to change a 
> > threads priority.  Now we used nice values from 19 to 0 which did not 
> > require root access.  In some cases a thread need to raise it's nice 
> > level and this would fail.  I also saw a note man renice(8) that said 
> > this bug exists.
> 
> hmm, SUS v3 seems to disagree.
> 
> "Only a process with appropriate privileges can lower its nice value."
> 
> and with this patch setpriority(2) is now inconsistent with nice(2)
> (albeit i don't know how much longer that interface will persist in arch
> independent portion of the kernel based on the comments surrounding it).

-- 
bill davidsen <[e-mail]>
  CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.

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