CHESS-ID3A-FAST

Accessing CHESS compute resources

You should not perform operations requiring signficant processing power or memory on the station computer. Instead, you can access the dedicated 3A workstation f2-analysis-2 or use the CHESS Compute Farm. To access these, you will use lnx201.classe.cornell.edu as a “stepping stone” into the rest of the network. Like the station computer, lnx201 has limited CPU/RAM resources, so only use it for lightweight operations such as filesystem navigation, basic text file editing/viewing, and ssh’ing to other places.

Options for performing analysis on CHESS compute resources:

• Log into workstation f2-analysis-2 (can NoMachine to this computer, or ssh from lnx20.classe.cornell.edu)
• Use the general nodes on the CLASSE compute Farm (available to anyone with a CLASSE ID)
• Use the FAST nodes on the CLASSE Compute Farm (available to whitelisted individuals; ask your beamline scientist for access)

CLASSE Compute Farm intro and how-to here.

Logging into an interactive terminal on the Compute Farm:

• ssh -Y [your CLASSE ID]@lnx201.classe.cornell.edu
  • Note: when ssh’ing from a Windows machine, you must install and run an X server (e.g. Xming) to enable graphics forwarding.
  • Alternatively: NoMachine into lnx201 (see NoMachine instructions here)
• qrsh -q interactive.q (puts you into an interactive terminal, operates just like a normal Linux terminal)
• Or if you have FAST node access: qrsh -q chess_fast_interactive.q

Note: both the analysis computer and the Compute Farm are shared resources. Please be aware of your usage and its impact on others.

• You can check the current load on f2-analysis-2 from the command line by running the command top (quick guide to this command here).
• You can check the current load on the FAST interactive nodes by running: qstat -f -u “*” -q chess_fast_interactive.q on lnx201.classe.cornell.edu. As a general rule please keep your typical use of the interactive nodes below 60 cores. Contact your beamline scientist if you anticipate needing resources beyond this level on a regular or extended basis.