High processor load on T60- after switching to battery

[davida]

Has anyone seen this problem?

After I remove the power supply, on some occassion the system goes into this strange state - oscillating load from 0 to 30% on one processor. Nothing appears to be running, so it is a kernel loop of some sort.

When in this stage I cannot shutdown or suspend. I have to hold down the power button and cold boot.

My guess is this is some kernel loop.

[Scratch]

In a show all Task Manager processes screen the system is showing System Idle process at 97-99% while this is occuring? I assume that this is the case when you indicate that nothing is running.

Sort the view to CPU acitivity top down and look for anything to momentarily jump to the top of the stack...even momentarily. This could be the culprit.

[davida]

yes, I have done that. What you see is the processor load oscillating from 0 to 30% or so - quite short period. You can see the effect of this on the mouse - which doesn't update it sposition smoothly.

Looking for a process that is causing it doesn't seem to indicate any culprit. If you plot kernel load as red, it shows as kernel load. I suspect the system is trying to put something in a low power mode and failing.

Originally I thought it had something to do with unplugging USB, but I have set the USB device to not power down, and it still does it.

And again, it stops the system from powering down, sleeping, etc.

More ideas?

[gator]

In the task manager, go to processes (2nd tab) and sort by memory usage. You should see which process is eating CPU cycles and maybe go on from there.

[Scratch]

Yes Gator. That's what I was referring to. The process that is creating the CPU load has to rise to the top of the list and should be identifiable. Perhaps it is generically showing as system or something that doesn't accurately or individually identify it?

I would start by killing all of the killable or non-essential systray processes then I would look for things that don't like PM like Explorer processes, defrag, VS, license management apps, etc. I've found some of the ATI processes to be trouble at times.

In Device Manager start disabling non-critical to base operation HW elements and continue to narrow the field.

Hopefully something will reveal itself and a driver upgrade or patch will be available to correct it.

[davida]

Sadly, none of these have revealed the problem. Nothing shows anything like the load that is present. Moreover, the load is showing as KERNEL mode, so I suspect it won't show in the task list.