Re: [9fans] killing processes

[Ronald G Minnich <rminnich@lanl.gov>]

Fco. J. Ballesteros wrote:

> Well, we could use Kill as said here, or even
> reboot the machine on saturdays 5am to make it clean,
> etc.

that's the one nice thing about a cluster node. You have lots of 'em, 
they can be single user. So just let one cpu user in to one cluster node 
at a time, and when they leave, reboot the node. If it's linuxbios the 
node is back in 10 seconds or so, and if it is a linuxbios+plan 9 node 
running xcpu, even faster than that (Plan 9 xcpu nodes boot in 1 second 
in Xen).


> However, the PCs have so much CPU today that they don't even
> feel the need for a CPU server.

And that's the fun part. The relative power relationship of terminal/cpu 
server got inverted about 10 years ago. In the kernel there is this 
comment about ' ... for the big boys'. But, nowadays, the desktop is way 
more powerful than any individual cluster node (well, if by nowadays, 
you mean, "starting in 1992..."). So the "big boy" is on your desk, and 
the toy computer is in your rack. It's just that there are so MANY toy 
computers in the racks ... the ants overwhelm the elephant.

And on the really Big Boy, i.e. the BG/L machine at livermore, the 
individual CPUs are running at clock rates that are "SO 1990s" -- 600 
Mhz! But, given 65K of them, well, you don't mind that they're slow.

In that sense, the 'cpu server' is outdated nomenclature.

ron