Hi Paul,

> Greetings!
> 
> I've just added a new node to our computing cluster and it's exhibiting
> some odd behavior. I'm afraid the background information is rather 
> long, but I don't want to leave anything out that may be useful.
> 
> Our cluster has a single node available on the public network (ssh 
> only) and eight (now nine) additional nodes on a private network (accessible
> only via ssh from the login node).
> 
> The original nodes are eight Sun V20z dual-Opteron boxes and one Sun
> V40z quad-Opteron box. RAM varies from 4G to 32G.
> 
> We recently added a new node based on a Penguin Altus 600 box with 
> two dual-core Opterons and 16G of RAM.
> 
> One monitoring tool I use is htop (from dag) and screen. I log into the
> login node, run screen, run htop, and then ^Ac and ssh to one of the
> compute nodes and run htop. I repeat until I have htop running on all
> nodes and can ^An and ^Ap to move around. I can detach the screen and
> re-attach it (from anywhere) whenever I want to have a quick look at
> what's going on.
> 
> I do this as a normal user.
> 
> When I follow this scenario and start htop on the new node, screen
> consumes between 20-30% CPU and never updates. top runs fine.
> 
> Furthermore, if I just ssh from the login node to the new compute node
> (screen not involved), htop behaves normally.
> 
> And further-furthermore, if I use the original scenario, open a 
> screen on the new node, su to root and run htop, htop behaves normally.

Which version of htop are you using? where did you install it from?

Michael.

> Any ideas, list-dwellers?
> 
> Cheers,
>  Pann
> -- 
> Pann McCuaig <[log in to unmask]>                212-854-8689
> Systems Coordinator, Economics Department, Columbia University
> Department Computing Resources:
>                http://www.columbia.edu/cu/economics/computing/
------- End of Original Message -------