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

From: Gene Heskett
Date: Tue Apr 24 2007 - 03:12:47 EST


On Tuesday 24 April 2007, Ingo Molnar wrote:
>* Gene Heskett <gene.heskett@xxxxxxxxx> wrote:
>> > Gene has done some testing under CFS with X reniced to +10 and the
>> > desktop still worked smoothly for him.
>>
>> As a data point here, and probably nothing to do with X, but I did
>> manage to lock it up, solid, reset button time tonight, by wanting
>> 'smart' to get done with an update session after amanda had started.
>> I took both smart processes I could see in htop all the way to -19,
>> but when it was about done about 3 minutes later, everything came to
>> an instant, frozen, reset button required lockup. I should have
>> stopped at -17 I guess. :(
>
>yeah, i guess this has little to do with X. I think in your scenario it
>might have been smarter to either stop, or to renice the workloads that
>took away CPU power from others to _positive_ nice levels. Negative nice
>levels can indeed be dangerous.
>
>(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.)
>
> Ingo

That sounds handy, particularly with idiots like me at the wheel...


--
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)
When a Banker jumps out of a window, jump after him--that's where the money
is.
-- Robespierre
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/