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Argonne Leadership Computing Facility

Arm DDT on Theta


You can use the latest Arm (Allinea) DDT debugger on the XC40 system (Theta).

There is no limit to the number of users; however, users have to share the available license tokens.

Modules and Soft keys

On Theta, for the latest version load the module forge/22.0.4. Note: When using the Arm Forge Remote Client, specify remote installation directory, "/soft/debuggers/forge-22.0.4-2022-08-02”. The Remote Client version must match.

On the systems managed with softenv (Cooley), use the soft key "+forge" for the latest version available. When using the Allinea Remote Client, specfiy remote installation directory "/soft/debuggers/forge".

Debugging with DDT

DDT may be started in two ways.

  1. Via Remote Client from your laptop or workstation (Recommended)
  2. Running the DDT client on a login node and displaying back to you via X11.

This method is best for remote use of DDT because the GUI client runs directly on your laptop or workstation. This has much lower remote bandwith requirements than the other method.

  1. Download the remote client at
  2. Note: There is a link near the bottom of the page for versions prior to the latest release. You have to use a similar version to the loaded forge module on Theta. For example, you may download Arm Forge Client 22.0.4 for the Theta module forge/22.0.4.
  3. Run the client on your local machine and select Remote Launch->Configure to set up a configuration to connect to the login node.
  4. Run your application on Theta with one of the following command lines:
  5. ddt --offline aprun -n 48 ./example
  6. ddt --connect aprun -n 48 ./example

Configure Remote launch settings Choose remote launch

On an interactive job mode, run your application with ddt --connect.

jkwack@thetalogin6:~> qsub -I -n 1 -t 60 -q debug-cache-quad -A Performance
Connecting to thetamom2 for interactive qsub...
Job routed to queue "debug-cache-quad".
Memory mode set to cache quad for queue debug-cache-quad
WARNING: Filesystem attribute not set for this job submission.
Wait for job 613897 to start...
Opening interactive session to 3834

jkwack@thetamom2:/lus/swift/home/jkwack> module load forge

jkwack@thetamom2:/lus/swift/home/jkwack> cd HPC_benchmarks/JKBench_GeoSeries

jkwack@thetamom2:~/HPC_benchmarks/JKBench_GeoSeries> ddt --connect aprun -n 64 ./Comp_GeoSeries_omp_cpu_cc_DP 4096 100

Accept request Run with Memory Debugging Details