Lubuntu freezing

[Lars Noodén]

On 29.08.2013 23:34, John Hupp wrote:
> 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.

I don't know of a way to get the kernel to freeze on demand.  It happens
irregularly, sometimes nearly a whole day in between failures.  Other
times a few hours.  I don't think yet that I can tie it to any
applications I have running.  I have very few open already and it does
not seem to matter which one is on top.  That could make the bisection
process take weeks.

Regards,
/Lars