Mac OS X freezes

[khansen@stat.be]

My G4 Powerbook running 10.4.5 has started to freeze (for about 1-3 seconds) at regular time intervals. Looking in the system log using Console, I get the following error message:

Mar 25 09:57:36 grue kernel[0]: AMS::infiniteIntTimerEventHandler ERROR have infinite interrupts, disabling

I get these messages every 5 minute. I have tried shuting down and restarting, but the problem persists.

Any ideas? How do I trace which process resulted in the error?

 

[IJ Reilly]

I don't know of any process that recurs every five minutes. Try leaving the Activity Monitor application running, sorted by CPU load, and see if you can pick up which process hits the top of the list when the slowdown occurs.

 

[khansen@stat.be]

thanks

but it did not help much. I was running iTunes (makes it easy to detect a freeze, since the music stops). Before and during the freeze, the top cpu jobs were
iTumes 5-8%
Safari 4%
kernel_taks 1.9-4%
WindowServer 2%
pm_tool 1.1-2%
There is some constant reshuffling, but nothing strange. During the freeze, nothing went over say 10% (and in fact none of them changed significantly).

 

[IJ Reilly]

I'm stumped by the cause, but if I were experiencing such a weird problem, my next step would be to reboot in Single User Mode and run Applejack.

 

[khansen@stat.be]

Problem solved (I believe)

Again, thanks for the help.

Short description: I had Google etc. for what AMS could be. After some hours spent searching various email lists on the Apple website and being frustrated, I found the following possibilities:
Audio Midi Setup
Apple Mail Server
Some hours were spent persuing this. Then I (forgot how) stumbled upon
http://www.osxbook.com/book/bonus/chapter10/ams/
which gave a new possibility:
Apple Motion Senser (Sudden Motion Senser)

I used the description on the website to disable to motion senser (note that the webpage is outdated in that the output from pmset -g lists the motion sensor as sms and not ams). That seemed to stop the error logs. But in the meantime I had shut down most or all of my services. I started/stopped the motion sensor a few times, and finally restarted (with sms on). Upon reboot I got exactly the same error messages, so I immediately disabled the motion sensor. That seemed to help....

Curious fact: using amstracker I get the position of my powerbook to be (0 0 0) - as if it was in free fall. Perhaps something have happened to my motion sensor?

Anyway, for now it seems as if the problem is "solved" by disabling the sensor using "sudo pmset -a ams 0" from a terminal.

 

[calebjohnston]

Sudden motion sensor protects your harddrive if your drop your computer though, doesn't it? (or it tries to at least)

 

[khansen@stat.be]

yes,

it does protect the harddrive against drops.

Having said that, I dropped my powerbook some time before Christmas and I had to reinstall (due to some bad sectors appearing in a crucial place on the harddisk - I was unable to solve the issue without reinstalling - and I did try various "boot of dvd diagnostics" and so on). Through some magic I was able to get my work of the machine, but basically the SMS did not work.

And it it generates errors/freezes the machine when it is running - I am not sure that I would trust it.

But agreed: it would be better to really solve the problem and get the SMS to work. Now that I know what might be wrong, I have (easily) found quite a few pages with information about the sensor. In the coming time I will dig through it and see if I can do a better diagnose.