Kernel Panic with heavy disk i/o while running on battery

Nathan Alan Souer nate at
Thu Feb 14 05:10:27 UTC 2008

The machine passed the memory test while on battery fine. however, while
on battery the checksum failed with i/o errors, it did complete the
checksum normally while on AC. I think my next step will be to try and
disable acpi, and to try and reproduce the error again. i suppose it could
be an issue with a flakey controller, but I havent seen any related issues
while I was running windows or ubuntu on the machine. if it isn't an issue
with power management, I guess I'll learn some kernel debugging.

> Nathan Alan Souer wrote:
>>> Nathan Alan Souer wrote:
>>>> In advance, I appreciate any help that anyone has to offer. When my
>>>> laptop
>>>> is running on battery and there is heavy i/o on the disk The machine
>>>> kernel panics and reboots. I have updated my base system to current
>>>> (7_releng) just a couple days ago in an effort to resolve this issue,
>>>> to
>>>> no change.
>>> I would start with a memory test program. I have seen similar things
>>> happen
>>> with broken memory.
>> the machine passes a full pass of memtest86+
> Just checking - you did the test in the same conditions (on battery
> power) as the crash?
> I have a suggestion that's a bit silly but it might help - can you boot
> of a live/fixit CD and calculate a hash of the drive's content, on and
> off AC power, to see if it's a hardware problem with the controller or
> the drive?
> (dd if=/dev/drive bs=1m | md5)

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