Interactive use of the PPPL cluster
There are two types of interactive use on the cluster,
non-exclusive and exclusive.
For non-exclusive access,
ssh
to
portal.pppl.gov. This is
an alias for several systems where logins are allocated to the
systems in a least loaded fashion. You use
portal
as you would any timesharing system, and you will be one of
possibly many users on the system.
So it is important to not run very high CPU or memory
intensive processes on portal. Instead, reserve a set of systems for your exclusive
use as detailed in the next section.
(The portal set of systems runs a 32 bit kernel. If you need to 64 bit environment
for compilations or test runs, ssh to portal64, an alias to a set of systems
running a 64 bit kernel and having the 64 bit runtime and build environment.)
For exclusive use of a system or systems, ssh to portal and execute the
command use.
This command will ask you a few questions about the number and types
of hosts you wish to use, then allocates those hosts for your
exclusive use from a pool of systems reserved for this type of use.
No other users will be allowed onto those
hosts. This provides you with uninterrupted and non-contentious
use of the hosts.
An exclusive interactive request is queued and scheduled just like
any other job, but when executed, the standard input, output, and
error streams of the job are connected through
your terminal session.