Lubuntu freezing

[John Hupp]

On 8/29/2013 4:20 PM, Gerry wrote:
> On 08/29/2013 01:36 PM, Lars Noodén wrote:
>> For the past 4 or 5 days Lubuntu has been freezing up on me at least
>> twice a day.  The symptoms are that everything appears to stop working.
>>   Even the mouse pointer won't move and I cannot switch to a console
>> (ctrl-alt-f1, etc).
>>
>> There's usually nothing in the system log at all but this last time I
>> get a bunch of nulls:
>>
>> Aug 29 13:17:01 mini2 CRON[3155]: (root) CMD (   cd / && run-parts
>> --report /etc/cron.hourly)
>> Aug 29 14:17:02 mini2 CRON[3291]: (root) CMD (   cd / && run-parts
>> --report /etc/cron.hourly)
>> ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^ 
>>
>> @^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
>>
>> The system crashed at 14:22, but there is nothing there in the log until
>> the (re)boot stage.
>>
>> I cannot get the system to freeze up on demand nor does it appear to be
>> connected to any particular application.  Yet it has been happening a
>> few times per day.  This is very unusual and I have had no similar
>> problems previously.  How can I gather more data on this the next time
>> it happens?
>>
>> Regards,
>> /Lars
>>
> I also have this problem. I switched to Xubu 12.04 LTS to evade the 
> 'the freeze' but since I upgraded to 12.04.3 'the freeze' returns.
>
>
>

If someone with the problem wants to pursue the prospect that this is a 
kernel issue, I think the definitive starting point is the procedure at 
https://wiki.ubuntu.com/Kernel/KernelBisection

Some of that looks pretty scary, but it seems to be the case that 
execution is within the reach of end-users like me.  The beauty of it is 
that the procedure can be expected to eventually identify the problem 
within a small chunk of code, which makes the developers' job of fixing 
the problem much easier.

I'm learning how to do this for the first time myself as I continue to 
pursue the root of a Flash video display problem that I posted about 
recently.