[Discuss] Very slow system, no idle, but nothing running

[Jerry Feldman]

On 04/22/2012 12:40 AM, David Kramer wrote:
> This is on my Ubuntu 10.04 laptop (Dell Latitude D820).  I don't know
> when it started, but every now and then I get into this condition where
> the UI seems almost completely locked up (the mouse may move a little
> occasionally  but the clock is frozen).  The hard drive light is often
> on for long periods of time, too.  But even when I can move the mouse,
> clicking on a window's close button does nothing.  Usually it never
> recovers from this state and I need to hard power down.
>
> The first couple of line from "top -c" read
> top - 00:13:25 up 6 days, 16:25,  6 users,  load average: 16.16, 19.67,
> 21.58
> Tasks: 194 total,   3 running, 189 sleeping,   0 stopped,   2 zombie
> Cpu(s): 13.3%us,  5.0%sy,  0.0%ni,  0.0%id, 81.4%wa,  0.2%hi,  0.2%si,
> 0.0%st
> Mem:   2060180k total,  2009288k used,    50892k free,     3488k buffers
> Swap:  1574328k total,  1492652k used,    81676k free,    62024k cached
>
>   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
>
>  6835 david     20   0  704m 184m 2352 R   20  9.2 142:15.54
> plugin-containe
> 19747 david     20   0  226m 170m 4868 S   15  8.5   4:07.80 geeqie
>
>  1185 root      20   0  231m  82m 6488 S    1  4.1 137:38.82 Xorg
>
>  6637 david     20   0 1174m 264m  11m D    1 13.2  99:02.16 firefox
>
> 20780 root      20   0  2548 1240  916 R    1  0.1   0:00.04 top
>
>     9 root      20   0     0    0    0 S    0  0.0   0:05.28 events/0
>
>
> So I don't see what the cores are so busy with. I was only able to get
> these numbers by eventually getting a text mode screen by pressing
> Ctr-Alt-F2 (get to a text shell) before it decided to do something.
> Swap space is low but should be sufficient.
>
> What can be locking up my laptop and causing the slowdown?
I think the first thing to do is to run a memory diagnostic. Also, checn
/proc/meminfo to see if the OS detected all your memory. (I agree with
Mark regarding the swap).
Also I've seen this problem before where the computer is very slow
including the mouse. If you are using NFS and have an issue with NFS it
can cause this problem. Or related, did you plug in a USB device and
unplug without unmounting it. The issue in these cases is that the OS
does a stat(2). Normally this should not cause a problem, but I have
seen it happen. Have you   run vmstat and iostat?

Another possible issue is that the Dell is out of warranty and it is
time to get another laptop :-)

Also, I would try to vacuum out the cat hairs. Even though you have it
on a cooling pad, the internal airflow is affected.

 

-- 
Jerry Feldman <gaf at blu.org>
Boston Linux and Unix
PGP key id:3BC1EB90 
PGP Key fingerprint: 49E2 C52A FC5A A31F 8D66  C0AF 7CEA 30FC 3BC1 EB90