Computer locking up after several days' uptime

[Derek Broughton]

Dotan Cohen wrote:

> A new Ubuntu user has 8.04 installed on an LG laptop. I do not have
> the machine nearby to check what the specific hardware is, but it is a
> fairly modern unit.
> 
> He is reporting that after three days' uptime the computer locks up.
> He did not have this problem in Windows. I asked if he could leave the
> machine running without programs for a few days' time to see if it is
> the OS or an application, but this is a work machine so he cannot do
> that.
> 
> Where can I begin troubleshooting? It may actually be a while before I
> get to the machine physically, so whatever I can ask over the phone or
> via SSH would help. Thanks!

Well, ssh is the first thing.  I've had systems (not for a long time now)
where the keyboard and/or display was locked, but I could actually log in
via ssh.  

Right now, I'd ssh in to see what is currently running.  Look particularly
for Java apps, and browser plugins.  I don't think I'd say they are
actually leaking memory, but long-running Java apps particularly have a
habit of growing to use all available memory and then swap-thrashing locks
everything up, or at least slows it to the point of unusability.
-- 
derek