Bug 102095 – kacpid takes all the CPU for himself and slows the installation to a halt on my laptop

• Status: RESOLVED FIXED
• Product: Gentoo Release Media

[Description Edoardo Costa 2005-08-11 02:37:21 UTC]

From what I can tell this happens on laptops only and on "minimal LiveCD 2005.0
and 2005.1".

My hardware: Laptop HP (Compaq) nc6120, 40GB HD, 1GB RAM - Installing Gentoo
From Minimal LiveCD 2005.1

kacpid takes the whole of the CPU for himself and leaves none for the
installation.  In top I can see it take 98% of the PCU.

I also tried to boot the LiveCD with all the options to turn devices and
services on and off but nothing did it.  From what I understand acpi is compiled
into the kernel and not as a module (maybe 'cause it can't be).  I also tried to
rmmod all modules that the laptop didn't need but that didn't help either.

My only work arround is to renice it to "19".  That seems to free the CPU when
needed but doesn't solve the problem.

Reproducible: Always
Steps to Reproduce:
1. Boot of the CD
2. Go past the point of chroot and start "scripts/bootstrap.sh" for example
although you might notice it way before
3. Use top to see kacpid hog the system

Actual Results:  
load of 95% to 100% continuously

Expected Results:  
PCU time for my install ;)

[Comment 1 Chris Gianelloni (RETIRED) 2005-08-12 10:44:05 UTC]

boot with acpi=off

[Comment 2 Bruno Redondi 2005-09-30 07:35:52 UTC]

I had a similar problem with my server. Try booting with the parameter 
"pci=routeirq". If it solves your problem have a look at 
http://bugzilla.kernel.org/show_bug.cgi?id=5312 

[Comment 3 Chris Gianelloni (RETIRED) 2005-09-30 08:05:47 UTC]

Bruno:  What kernel version were you experiencing this with?

[Comment 4 Bruno Redondi 2005-09-30 13:42:32 UTC]

I dont remember, I think it was 2.6.10, but the issue is still present in  
gentoo-sources-2.6.12-r10 and in vanilla-sources-2.6.12.5.  
The patch in http://bugzilla.kernel.org/show_bug.cgi?id=5312 solved the problem 
with my cpqphp hot plug controller. 

[Comment 5 Chris Gianelloni (RETIRED) 2005-09-30 14:02:58 UTC]

Hrrrmn... I'm mostly wondering because I've seen this myself, and turning off
ACPI helped on my machine.  I don't have a Compaq Hotplug controller, however,
as this is a pretty "normal" home-built Opteron box.

[Comment 6 Bruno Redondi 2005-10-02 00:45:56 UTC]

The driver is bad-named because it applyes also to other hotplug controllers, 
infact my motherboard is intel with intel chipset. Many pci controllers are 
hotplug capable (logic layer) alsa if the motherboard does not permit hotplug 
(electric layer). 

[Comment 7 Chris Gianelloni (RETIRED) 2005-11-21 07:00:36 UTC]

Can you please test the 2005.1-r1 CD that was just released?

[Comment 8 Bruno Redondi 2006-01-24 10:16:27 UTC]

My motherboard works fine with 2.6.15 (upstream fixed)

[Comment 9 Chris Gianelloni (RETIRED) 2006-03-14 12:42:26 UTC]

This should be fixed in 2006.0's media.  Please REOPEN if this is not the case.