Re: [REPORT] cfs-v4 vs sd-0.44

From: Gene Heskett
Date: Tue Apr 24 2007 - 10:38:52 EST

On Tuesday 24 April 2007, Ingo Molnar wrote:
>* David Lang <david.lang@xxxxxxxxxxxxxxxxxx> wrote:
>> > (Btw., to protect against such mishaps in the future i have changed
>> > the SysRq-N [SysRq-Nice] implementation in my tree to not only
>> > change real-time tasks to SCHED_OTHER, but to also renice negative
>> > nice levels back to 0 - this will show up in -v6. That way you'd
>> > only have had to hit SysRq-N to get the system out of the wedge.)
>> if you are trying to unwedge a system it may be a good idea to renice
>> all tasks to 0, it could be that a task at +19 is holding a lock that
>> something else is waiting for.
>Yeah, that's possible too, but +19 tasks are getting a small but
>guaranteed share of the CPU so eventually it ought to release it. It's
>still a possibility, but i think i'll wait for a specific incident to
>happen first, and then react to that incident :-)
> Ingo

In the instance I created, even the SysRq+b was ignored, and ISTR thats
supposed to initiate a reboot is it not? So it was well and truly wedged.

Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
I use technology in order to hate it more properly.
-- Nam June Paik
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