Choppy mouse / video on laptop

[dsr at tao.merseine.nu (dsr at tao.merseine.nu)]

On Wed, Jan 08, 2003 at 12:58:20PM -0500, Duane Morin wrote:
> I'm hoping that maybe somebody can give me a lesson in how to read a 
> system's load, be it memory, CPU, swap or otherwise.  I've got a 128M 

CPU load is defined as the ratio of the number of processes ready to run
to the number of processes that have been run. On a single processor
system, a CPU load of 1.0 means that every process is being completed
just-in-time, on average.

> It feels like the machine is constantly writing to disk.  'top' tells me 
> that I'm using about 80M out of 256M.  Memory usage ranges, sometimes 
> going as high as 120M out of 128M.  The thing that I don't know how to 
> read is under CPU state, where it says 55% System.  Is that bad?  The load 
> average is in the 5.x range.

Very bad. 5.x means that there is five times as much work as the
processor can handle. While this may be acceptable for non-interactive
usage, it's disastrous for interactive applications.

> [As a baseline, I just rebooted the machine and opened a terminal.  I 
> still get 122M/128M memory used, now it's 1M/256M swap, and although 
> system CPU briefly touched 50%, it now sits at 0.9%.  When running 
> earlier, the system sat between 43-55% constantly. Load fell to 0.07, 
> 0.32, 0.17.]

Normally, a freshly booted machine given some time to calm down will
have a load average around 0.0 - 0.05.

> Can somebody give me some tips about where to look for culprits?  If I 
> think that it is spending a huge amount of time swapping, can I measure 
> that and compare it against what it should be doing?  

Send us, or me:

the output of top under your normal running conditions
the output of pstree under your normal running conditions

You could almost certainly use some more RAM, by the way. 

-dsr-


-- 
Network engineer looking for work in Boston area.
Resume at http://tao.merseine.nu/~dsr/