Couple of (re)nice questions

From: Random Penguin (nonexistent2032_at_yahoo.co.uk)
Date: 09/08/05 

Date: 8 Sep 2005 03:51:58 -0700

Hi guys. I've got a couple of questions about nice/renice....

1) Is it possible for root to increse the range of nice/renice from -10
and 19?

2) I notice that a normal user can lower the priority but not raise it,
even if it were to a value lower than what it originally was (doesn't
make sense...)

E.g.

user@work:~> renice 19 12345
12345: old priority 0, new priority 19

user@work:~> renice 18 12345
renice: 12345: setpriority: Permission denied

As root, can you specify that normal users cn raise a nice level to
(say) 0?

3) I remotely raised the nice level of a CPU intensive process to -5.
Soon afterward the remote connection failed to respond and I can't log
into the computer anymore :-(. The computer however is responding to
pings. Should I call up a colleague at work and tell them to restart
the machine? I have no idea when it will finish, even if it hasn't
crashed the machine.

4) Is there a way of automatically setting nice priorities through a
script of some kind?

I've found that my jobs get done faster if I get each CPU to solve them
serially rather than in parallel. The reason why I just execute a list
of them instead of one by one is because I don't know when each one
will finish and it saves time to not let the CPU idle at all.

So what I'd like to do is renice 1 task to 0 priority, the rest to 19.
When that task finishes, a pre-assigned one gets reniced to 0.

Thanks.

Relevant Pages

  • Re: Controlling CPU utilization of a process
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    (comp.unix.solaris)
  • renice IO operations
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    (SunManagers)
  • Re: [PATCH] Nicks scheduler policy v12
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    (Linux-Kernel)
  • Re: Parallel Common-Lisp with at least 64 processors?
    ... loadavg: Command not found. ... $ renice +4 13589 ... old priority 0, new priority 4 ... If I have a lot of little tasks to execute, I put them into a PROGN ...
    (comp.lang.lisp)
  • Re: [RFD] nice attribute for executable files
    ... > renice some tasks until the more important work is done. ... web server runs as user www. it spawns perl interpreter that root wants ... webmaster is malicious person; i know, ... send the line "unsubscribe linux-kernel" in ...
    (Linux-Kernel)